Overview|V4.2.5|OceanBase Database|docs|OceanBase Documentations

Variable	Description
validate_password_check_user_name	Specifies whether to allow the password to be the same as the username.
validate_password_length	Specifies the minimum length of the password.
validate_password_mixed_case_count	Specifies the minimum number of uppercase and lowercase letters in the password.
validate_password_number_count	Specifies the minimum number of digits in the password.
validate_password_policy	Specifies the password check policy.
validate_password_special_char_count	Specifies the minimum number of special characters in the password.
ob_tcp_invited_nodes	Specifies the IP address whitelist for the tenant. Supports the use of the percent sign (%), underscore (_), and multiple IP addresses separated by commas. Supports IP list matching, mask matching, and fuzzy matching.
default_password_lifetime	Specifies the password expiration time.
block_encryption_mode	Specifies the encryption algorithm used in the aes_encrypt and aes_decrypt functions.
sql_safe_updates	Specifies whether to enable the SQL safe mode of MySQL. The default value is OFF.
lower_case_table_names	Specifies whether to be case-sensitive.
super_read_only	Controls the read and write permissions of the database. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
check_proxy_users	Specifies whether to enable or disable checks for proxy user mappings. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_aws_cmk_id	Specifies the customer master key (CMK) ID of the Amazon Web Services (AWS) Key Management Service (KMS). Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_aws_region	Specifies the AWS region for the Key Management Service. The default value is `us-east-1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_encrypted_file_data	Specifies the path of the file used to store the encrypted key. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_encrypted_file_password	Specifies the password used to encrypt the key file. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_file_data	Specifies the file path used to store the key. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_okv_conf_dir	Specifies the path of the Oracle Key Vault configuration directory. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
keyring_operations	Specifies the key operation mode, such as read and write. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect and no error will be reported.
max_connect_errors	Specifies the maximum number of connection errors. After this number is exceeded, the user is prohibited from connecting. The default value is `100`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
mysql_firewall_mode	Specifies the working mode of the MySQL firewall. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
mysql_firewall_trace	Specifies whether to enable or disable firewall tracing. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
mysql_native_password_proxy_users	Specifies whether to support proxy users for native password authentication. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
net_retry_count	Specifies the number of network retries. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
old_passwords	Specifies the password hashing method used by functions. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
secure_auth	Specifies whether to use new passwords for secure authentication. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
sha256_password_proxy_users	Specifies whether to support proxy users for SHA-256 password authentication. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
show_compatibility_56	Specifies whether to be compatible with MySQL 5.6. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
validate_password_dictionary_file	Specifies the path of the dictionary file for password validation. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
auto_generate_certs	Specifies whether to automatically generate SSL key and certificate files in the data directory. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
disconnect_on_expired_password	Specifies whether to disconnect the connection when the password expires. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
have_dynamic_loading	Specifies whether to support dynamic loading of plugins. The default value is `YES`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
keyring_aws_conf_file	Specifies the path of the AWS keyring configuration file. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
keyring_aws_data_file	Specifies the path of the AWS keyring data file. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
lower_case_file_system	Specifies whether to run MySQL on a case-insensitive file system. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
max_digest_length	Specifies the maximum memory in bytes that each session can occupy. The default value is `1024`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndbinfo_database	Specifies the database for NDB information. The default value is `ndbinfo`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
sha256_password_private_key_path	The path where the private key for SHA-256 password authentication is stored. The default value is `private_key.pem`. Note This variable is available only for compatibility with MySQL 5.7. You can query the value but cannot set it.
sha256_password_public_key_path	The path where the public key for SHA-256 password authentication is stored. The default value is `public_key.pem`. Note This variable is available only for compatibility with MySQL 5.7. You can query the value but cannot set it.
skip_show_database	Whether to allow only users with the SHOW DATABASES privilege to execute the SHOW DATABASES statement and display all database names. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. You can query the value but cannot set it.

Variable name	Description
version_comment	Displays the version information of the OBServer node.
version	1. The value of this variable indicates the version of the server.
ob_proxy_global_variables_version	Sets the latest version of global variables that the OBServer node returns to the OBproxy node.
ob_enable_transmission_checksum	Sets whether to enable the data packet checksum between the ODP and OBServer nodes. This option takes effect immediately after being set.
ob_compatibility_control	Controls the behavior mode when there are compatibility conflicts between MySQL 5.7 and MySQL 8.0. Specify the compatibility mode when you create a tenant. You cannot modify the mode after the tenant is created.
ob_compatibility_version	The compatible OceanBase Database version for the features that change the product behavior. Specify the compatible version when you create a tenant. You cannot change the compatible version after the tenant is created.
ob_security_version	The OceanBase Database version that is compatible with the security feature. Specify the compatible version when you create a tenant, and this parameter cannot be modified after the tenant is created.
new	Sets whether to enable some behaviors introduced in MySQL 4.1 in MySQL 4.0 and ensure backward compatibility. The default value is `OFF`. Note This variable is available only for MySQL 5.7 backward compatibility. You can query and set the variable, but the variable setting does not take effect.
version_tokens_session	The variable to set the version tokens for a session. Its default value is `NULL`, which means all server versions are matched. Note This variable is only for compatibility with MySQL 5.7. The related functions are not supported, but you can query and modify it. The modifications do not take effect.

Variable	Description
debug	For debugging. The default value is `d:t:i:o,/tmp/mysqld.trace`. Note This variable is for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable. The setting does not trigger an error, but has no effect.
ob_global_debug_sync	Specifies a debug synchronization point. When you set this variable, all sessions are affected.

Variable	Description
query_cache_size	Specifies the amount of memory allocated for storing query results that are not yet used.
query_cache_type	Specifies the query cache type.
ob_query_timeout	Specifies the query timeout.
net_buffer_length	Specifies the maximum size of an SQL query that can be accepted by an OBServer node.
read_only	Specifies whether the tenant is in read-only mode.
ob_read_consistency	Specifies the read consistency level.
ob_max_read_stale_time	The maximum delay threshold (in microseconds) for weak-consistency reads.
net_read_timeout	Specifies the number of seconds to wait for other data before interrupting a read.
net_write_timeout	Specifies the number of seconds to wait for a block to be written to the connection before interrupting a write.
ob_enable_index_direct_select	Specifies whether to allow users to directly query index tables.
ob_enable_aggregation_pushdown	Specifies whether to allow aggregation operations to be pushed down.
ob_enable_jit	Specifies the JIT execution engine mode.
sql_throttle_network	Specifies the request queuing time. If the request queuing time is greater than or equal to this value, the query is not allowed to be executed.
parallel_servers_target	Specifies the conditions for queuing large queries on each server.
cte_max_recursion_depth	Specifies the maximum recursion depth for common table expressions (CTEs). The server terminates the execution of any operation that exceeds this CTE value.
regexp_stack_limit	Specifies the maximum available memory for the internal stack used in regular expression matching operations.
regexp_time_limit	Specifies the time limit for regular expression matching operations.
big_tables	Specifies whether to enable large table queries. If enabled, you can use the features of large MyISAM tables. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_prune_level	Controls the behavior of the query optimizer. The optimizer skips unnecessary query plans based on the estimated number of rows accessed from each table, thereby reducing query compilation time. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_search_depth	Specifies the depth of query execution plan search performed by the optimizer. The default value is `62`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_switch	Specifies the behavior options of the optimizer to enable or disable specific features. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_trace	Enables the query optimizer trace feature for debugging and analyzing query execution plans. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_trace_features	Specifies the features to include in the optimizer trace. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
optimizer_trace_limit	This variable specifies the maximum number of optimizer trace entries. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
optimizer_trace_max_mem_size	This variable specifies the maximum memory usage of the optimizer trace. The default value is `16384`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
optimizer_trace_offset	This variable specifies the offset of the optimizer trace. The default value is `-1`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
range_optimizer_max_mem_size	This variable specifies the maximum memory usage of the range optimizer. The default value is `8388608`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
rewriter_enabled	This variable specifies whether to enable the query rewrite feature. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
rewriter_verbose	This variable specifies whether to enable verbose mode for debugging the query rewrite process. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
show_create_table_verbosity	This variable specifies whether to display the row format when a table is created. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
sql_big_selects	This variable specifies whether to enable large queries. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.

Variable	Description
event_scheduler	Indicates whether the event scheduler is enabled and running on the server.

Variable	Description
ob_create_table_strict_mode	Specifies the strict mode for table creation.
ob_default_replica_num	Specifies the default number of replicas for each table in a cluster.
master_info_repository	Specifies whether to record metadata to the mysql table in the InnoDB system database or to store it as a file in the data directory. The default value is `FILE`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
replication_optimize_for_static_plugin_config	Specifies whether to enable shared locks to improve the performance of semi-synchronous replication. The default value is `OFF`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
replication_sender_observe_commit_only	Specifies whether to enable limited callbacks to improve the performance of semi-synchronous replication. The default value is `OFF`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
rpl_semi_sync_slave_enabled	Specifies whether to enable semi-synchronous replication on a replica. The default value is `OFF`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
rpl_semi_sync_slave_trace_level	Specifies the debug trace level for semi-synchronous replication on a replica. The default value is `32`, which indicates the network waiting level. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
rpl_stop_slave_timeout	Specifies the time to wait before the STOP SLAVE statement times out, in seconds. The default value is `31536000`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_checkpoint_group	Specifies the maximum number of transactions that can be processed by the multi-threaded replication threads before a checkpoint operation is called to update the progress status. The default value is `512`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_checkpoint_period	Specifies the maximum time allowed before a checkpoint operation is called to update the status of the multi-threaded replication threads, in milliseconds. The default value is `300`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_compressed_protocol	Specifies whether to use the compression of the source or replica protocol when both the source and replica support compression. The default value is `OFF`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable.
slave_exec_mode	Specifies how the replication threads resolve conflicts and errors during replication. Setting this variable to `IDEMPOTENT` suppresses errors for duplicate and missing keys; setting it to `STRICT` does not suppress these errors. The default value is `STRICT`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_max_allowed_packet	Specifies the maximum size of an SQL or I/O thread data packet, in bytes. The default value is `1073741824`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_net_timeout	Specifies the time to wait for more data or a heartbeat signal from the source before the replica considers the connection to be disconnected, aborts reading, and attempts to reconnect, in seconds. The default value is `60`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable.
slave_parallel_type	Specifies the type of parallel execution for replication transactions when multi-threaded replication is enabled. The default value is `DATABASE`. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_parallel_workers	Specifies the number of threads to execute replication transactions in parallel. The default value is `0`, which indicates that parallel execution of replication transactions is disabled. Note This variable is only used for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the settings will not take effect.
slave_pending_jobs_size_max	For multi-threaded replication, specifies the maximum length of the work queue for storing unapplied events, in bytes. The default value is `16777216`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
slave_preserve_commit_order	For multi-threaded replication, specifies whether to commit transactions in the order they are replayed from the logs. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
slave_rows_search_algorithms	Specifies the algorithm used by the replica to search for related rows. The default value is `TABLE_SCAN,INDEX_SCAN`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
slave_sql_verify_checksum	Specifies whether to verify data using the checksum read from the replayed logs. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
slave_transaction_retries	Specifies the number of times the system automatically retries a transaction that fails due to a deadlock or because the transaction execution time exceeds the value specified by the `innodb_lock_wait_timeout` variable. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
slave_type_conversions	Specifies the type conversion mode for replicas when using row-based replication. The default value is empty, indicating that type conversion between the source and replica is disabled. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
sql_slave_skip_counter	Specifies the number of events from the source that the replica should skip. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
skip_slave_start	Specifies whether to skip starting the replication thread when the replica server starts. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
slave_load_tmpdir	Specifies the directory name for creating temporary files on the replica. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
slave_skip_errors	Specifies which errors to skip during replication. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
max_relay_log_size	Specifies the threshold for automatically rotating relay log files. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
relay_log_info_repository	Specifies whether to store the application metadata repository of the replica server as an InnoDB table in the mysql system database or as a file in the data directory. The default value is `FILE`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
relay_log_purge	Specifies whether to enable or disable automatic purging of unnecessary relay log files. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
sync_relay_log	Specifies how to synchronize relay logs to relay log files. When the value of this variable is greater than 0, the MySQL server synchronizes relay logs to disk after every `sync_relay_log` events are written to the relay log. The default value is `10000`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
sync_relay_log_info	Specifies how to synchronize the position information of the application relay log to a file or table. Setting this variable immediately takes effect for all replication channels, including those that are running. The default value is `10000`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect but does not return an error.
sync_master_info	The impact of this variable on a replica depends on whether the `master_info_repository` parameter is set to FILE or TABLE. The default value is `10000`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable. However, the setting does not take effect.
init_slave	This variable is similar to init_connect. It specifies the string to be executed by the replica when the SQL thread of the replica is started. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable. However, the setting does not take effect.
log_slow_slave_statements	If the slow query log is enabled on the replica, specifies whether to record slow SQL statements executed by the replication threads to the slow query log. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable. However, the setting does not take effect.
report_host	The hostname or IP address of the source to be reported during the registration of the replica. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
report_password	The password of the replication user account to be reported during the registration of the replica. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
report_port	The TCP/IP port number used to connect to the replica, to be reported during the registration of the replica. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
report_user	The username of the account to be reported during the registration of the replica. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log	The name of the relay log. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log_basename	The name and full path of the relay log. The default value is `/usr/local/mysql/data/obrd-relay-bin`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log_index	The name of the relay log index file. The default value is `/usr/local/mysql/data/obrd-relay-bin.index`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log_info_file	The name of the file that records information about the relay log. The default value is `relay-log.info`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log_recovery	If this variable is enabled, the relay log is automatically recovered when the replica is started. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
relay_log_space_limit	The maximum capacity of all relay logs, in bytes. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.

Variable name	Description
rpl_semi_sync_master_enabled	Specifies whether to enable semi-synchronous replication on the source. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
rpl_semi_sync_master_timeout	Specifies the time in milliseconds that the source waits for a replica to acknowledge a commit. The default value is `10000`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
rpl_semi_sync_master_trace_level	Specifies the debug trace level of semi-synchronous replication on the source. The default value is `32`, which indicates the network waiting level. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
rpl_semi_sync_master_wait_for_slave_count	Specifies the number of replicas that must acknowledge a transaction before the source continues. The default value is `1`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
rpl_semi_sync_master_wait_no_slave	Specifies whether the source waits for a timeout (set by the `rpl_semi_sync_master_timeout` variable) even if the number of replicas is less than the value set by the `rpl_semi_sync_master_wait_for_slave_count` variable. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
rpl_semi_sync_master_wait_point	Specifies the point at which the semi-synchronous source waits for a replica to acknowledge a transaction before returning the status to the client that submitted the transaction. The default value is `AFTER_SYNC`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.

Variable name	Description
enforce_gtid_consistency	Specifies whether to use GTID-safe statements to enforce GTID consistency. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
gtid_executed_compression_period	Specifies the frequency at which the server compresses the `gtid_executed` value. The default value is `1000`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
gtid_mode	Specifies whether to enable GTID-based logging and the type of log transactions. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
gtid_purged	Specifies the GTID set of all transactions that have been committed on the server but are not present in any binary log file on the server. The default value is `NULL`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.

Variable name	Description
recyclebin	Specifies whether to enable the recycle bin.
ob_enable_truncate_flashback	Specifies whether to enable truncate flashback.

Variable name	Description
ob_enable_pl_cache	Controls whether to enable the PL cache module.
ob_enable_plan_cache	Specifies whether to enable the plan cache.
ob_plan_cache_percentage	Specifies the percentage of memory that can be used by the plan cache.
ob_plan_cache_evict_high_percentage	Specifies the percentage of memory that triggers the eviction of the plan cache.
ob_plan_cache_evict_low_percentage	Specifies the percentage of memory at which the eviction of the plan cache stops.
ob_bnl_join_cache_size	Specifies the amount of data cached in a single Batch Nested Loop Join (BNLJ) operation.
stored_program_cache	Specifies the number of stored procedures and functions cached. The default value is `256`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
table_open_cache_instances	Specifies the number of table cache instances opened. The default value is `16`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.

Variable name	Description
interactive_timeout	Specifies the number of seconds that the server waits for activity before closing an interactive connection.
wait_timeout	Specifies the number of seconds that the server waits for activity before closing a noninteractive connection.
group_concat_max_len	Specifies the maximum length of the result of the `GROUP_CONCAT()` function.

Variable name	Description
session_track_gtids	Controls whether the server returns GTID to the client. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
session_track_transaction_info	Controls whether the server tracks the transaction status of the current session. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.

Variable	Description
innodb_change_buffering_debug	The debug level for changing the InnoDB buffer. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_compress_debug	The debug level for adjusting and controlling the compression behavior. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_disable_resize_buffer_pool_debug	Whether to enable the size adjustment of the InnoDB buffer pool. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_fil_make_page_dirty_debug	The debug level for dirtying the specified number of pages in InnoDB. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_limit_optimistic_insert_debug	The number of records on each B-tree page. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_merge_threshold_set_all_debug	The percentage of full pages for an index. The default value is `50`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_saved_page_number_debug	The number of pages saved in InnoDB for debugging. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_strict_mode	The SQL check mode for specific syntax.
innodb_stats_persistent	Whether to persist InnoDB index statistics to disk.
innodb_trx_purge_view_update_only_debug	The debug level for updating only the purge view during transaction cleanup. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_trx_rseg_n_slots_debug	The number of slots in the transaction rollback segment. Each slot stores transaction rollback information. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_replication_delay	The delay time of the replication thread on the replica server when the value of the `innodb_replication_delay` variable is reached. The unit is milliseconds. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_force_recovery	The crash recovery mode for repairing data of the InnoDB storage engine. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
innodb_flush_log_at_timeout	The interval for flushing logs. The unit is seconds. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_flush_log_at_trx_commit	The balance between the strict compliance with ACID characteristics and higher performance. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_log_checkpoint_now	The debug option for forcing InnoDB to write a checkpoint. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_log_checksums	Whether to enable checksums for Redo log pages. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_log_compressed_pages	Whether to save compressed pages in Redo logs. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
innodb_log_write_ahead_size	The size of the redo log write-ahead block, in bytes. The default value is `8192`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_max_undo_log_size	The threshold size of the undo tablespace. The default value is `1073741824`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_online_alter_log_max_size	The maximum size of the temporary log file used during online DDL operations on a table, in bytes. The default value is `134217728`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_undo_log_truncate	When this variable is enabled, the undo tablespace exceeding the threshold defined by the `innodb_max_undo_log_size` variable is marked for truncation. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_undo_logs	The number of rollback segments used by InnoDB. The default value is `128`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_rollback_on_timeout	Specifies whether to abort and roll back the entire transaction when a transaction times out. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
innodb_api_disable_rowlock	Specifies whether to disable row locks when InnoDB Memcached executes DML operations. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
innodb_autoinc_lock_mode	The locking mode for generating auto-increment values. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
innodb_read_only	Specifies whether to start InnoDB in read-only mode. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
innodb_api_bk_commit_interval	The frequency at which InnoDB Memcached automatically commits connections. The default value is `5`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_api_trx_level	The transaction isolation level for queries processed by the Memcached interface. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_support_xa	Specifies whether to enable XA transactions for InnoDB. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_sync_debug	Specifies whether to enable synchronization debugging checks for the storage engine. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
innodb_adaptive_flushing	Specifies whether to dynamically adjust the rate at which dirty pages are flushed from the buffer pool based on the workload. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_adaptive_flushing_lwm	The minimum percentage of redo log capacity for adaptive flushing. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_adaptive_hash_index	Specifies whether to enable the InnoDB adaptive hash index mechanism. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_adaptive_max_sleep_delay	The delay time that InnoDB automatically adjusts based on the current workload. The default value is `150000`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_autoextend_increment	The increment size for extending InnoDB data files, in MB. The default value is `64`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting has no effect.
innodb_background_drop_list_empty	This variable specifies whether to perform operations such as dropping tables or indexes when the background task list is empty. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_dump_at_shutdown	This variable specifies whether to dump the contents of the InnoDB buffer pool to disk when the database is shut down, so that the contents can be quickly restored during the next startup. The default value is `ON`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_dump_now	This variable specifies whether to immediately dump the contents of the InnoDB buffer pool. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_dump_pct	This variable specifies the percentage of the buffer pool content to be dumped. The default value is `25`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_filename	This variable specifies the format of the file that stores the tablespace IDs and page IDs generated in the buffer pool. The default value is `ib_buffer_pool`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_load_abort	This variable specifies whether to terminate the ongoing buffer pool loading operation. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_load_now	This variable specifies whether to immediately load the previously dumped buffer pool content. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_buffer_pool_size	This variable specifies the size of the InnoDB buffer pool. The default value is `134217728`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_change_buffer_max_size	This variable specifies the maximum percentage of the InnoDB buffer pool that can be occupied by the change buffer. The default value is `25`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_change_buffering	This variable specifies the change buffering strategy for InnoDB, such as insert and delete operations. The default value is `all`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_checksum_algorithm	This variable specifies the checksum algorithm used to generate and verify the checksums of disk blocks stored in the InnoDB tablespace. The default value is `crc32`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_cmp_per_index_enabled	This variable specifies whether to collect compression statistics for each index. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_commit_concurrency	This variable specifies the maximum number of threads that can perform commit operations simultaneously. The default value is `0`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_compression_failure_threshold_pct	This variable specifies the threshold percentage for table compression failure rate. The default value is `5`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_compression_level	This variable specifies the zlib compression level for compressing tables and indexes in InnoDB. The default value is `6`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_compression_pad_pct_max	This variable specifies the maximum percentage of each compressed page that can be reserved as available space. The default value is `50`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_concurrency_tickets	This variable specifies the number of concurrent threads for InnoDB. The default value is `5000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_default_row_format	This variable specifies the default row format for InnoDB tables and temporary tables. The default value is `DYNAMIC`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the settings do not take effect and no error is returned.
innodb_disable_sort_file_cache	Specifies whether to disable the system cache for merge sort temporary files. The default value is `OFF`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_file_format	Specifies the InnoDB file format for tablespace files. The default value is `Barracuda`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_file_format_max	Specifies the file format tag for the system tablespace. The default value is `Barracuda`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_file_per_table	Specifies whether to create tables in the system tablespace. The default value is `ON`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_fill_factor	Specifies the percentage of space to fill on each B-tree page during the construction of a sorted index. The default value is `100`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_flush_neighbors	Specifies whether to flush other dirty pages in the same range when you flush pages from the InnoDB buffer pool. The default value is `1`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_flush_sync	Specifies whether to immediately write data to disk when you write data to the InnoDB buffer pool. The default value is `ON`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_flushing_avg_loops	Specifies the average number of loops for InnoDB when you write data to the buffer pool. The default value is `30`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_lru_scan_depth	Specifies the depth of the page cleaner thread in each buffer pool instance for scanning the LRU page list in the buffer pool to find dirty pages to be flushed. The default value is `1024`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_max_dirty_pages_pct	Specifies the maximum percentage of dirty pages in the InnoDB buffer pool. The default value is `75`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_max_dirty_pages_pct_lwm	Specifies the minimum percentage of dirty pages to be pre-flushed. The default value is `0`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_max_purge_lag	Specifies the maximum delay time between the transaction commit and the complete purge of the transaction. The default value is `0`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
innodb_max_purge_lag_delay	Specifies the maximum delay time (in microseconds) for delaying the execution of INSERT, UPDATE, and DELETE operations when the `innodb_max_purge_lag` threshold is exceeded. The default value is `0`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting does not take effect.
ignore_builtin_innodb	Specifies whether to ignore the built-in InnoDB storage engine. The default value is `NO`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
innodb_buffer_pool_chunk_size	Specifies the size of an InnoDB buffer pool chunk. The default value is `134217728`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
innodb_buffer_pool_instances	Specifies the number of InnoDB buffer pool instances. The default value is `1`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
innodb_buffer_pool_load_at_startup	Specifies whether to automatically load the buffer pool at startup. The default value is `1`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
innodb_checksums	Specifies whether to use checksums for all tables read from disk. The default value is `ON`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
innodb_doublewrite	Specifies whether to store all data twice in InnoDB. First, the data is stored in the doublewrite buffer, and then it is stored in the actual data file. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
innodb_file_format_check	Specifies whether to enable InnoDB to check the file format flags in the system tables. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
innodb_flush_method	Specifies the method for flushing data to the InnoDB data and log files. The default value is `NULL`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
innodb_force_load_corrupted	Specifies whether to load tables marked as corrupted during InnoDB startup. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
innodb_page_size	Specifies the page size of the InnoDB tablespace. The default value is `16384`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
innodb_version	Specifies the InnoDB version. The default value is `5.7.38`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query it, but you cannot set it.
information_schema_stats_expiry	Specifies the number of seconds for the server to obtain data from the storage engine and replace the cached data. The default value is `86400`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
low_priority_updates	Specifies whether to control the priority of INSERT, UPDATE, DELETE, and REPLACE statements. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
max_error_count	Specifies the maximum number of errors, warnings, and notifications that the server can store in the diagnostic context. The default value is `64`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
max_insert_delayed_threads	Specifies the maximum number of threads for executing INSERT DELAYED statements. The default value is `20`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_monitor_disable	This variable acts as a switch to disable specific metrics counters. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_monitor_enable	This variable acts as a switch to enable specific metrics counters. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_monitor_reset	This variable acts as a switch to reset specific metrics counters to 0. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_monitor_reset_all	This variable acts as a switch to reset all values (maximum, minimum, etc.) of specific metrics counters to 0. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_old_blocks_pct	Specifies the approximate percentage of the old data blocks in the InnoDB buffer pool. The default value is `37`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_old_blocks_time	Specifies the time in milliseconds that a block must remain in the old sublist after its first access before it can be moved to the new sublist. The default value is `1000`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_purge_batch_size	Specifies the number of undo log pages to parse and process at a time from the history list. The default value is `300`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_purge_rseg_truncate_frequency	Specifies the frequency at which to truncate rollback segments. The default value is `128`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it. Setting this variable does not generate an error, but the setting does not take effect.
innodb_random_read_ahead	Specifies whether to enable random read-ahead to optimize I/O for the InnoDB storage engine. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_read_ahead_threshold	Specifies the number of pages that must be read sequentially from a segment before asynchronous reads from the next segment are initiated. The default value is `56`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_rollback_segments	Specifies the number of rollback segments for transactions that generate undo logs. The default value is `128`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_spin_wait_delay	Specifies the interval between spin lock waits. The default value is `6`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_status_output	Specifies whether to enable regular output from the standard InnoDB monitor. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_status_output_locks	Specifies whether to enable InnoDB lock monitoring. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_sync_spin_loops	Specifies the number of times a thread waits for an InnoDB mutex to be released before it is suspended. The default value is `30`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_fast_shutdown	Specifies the shutdown mode for the InnoDB storage engine. The default value is `1`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_io_capacity	Specifies the approximate number of IOPS that can be performed per second by background tasks for the InnoDB storage engine. The default value is `200`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_io_capacity_max	Specifies the maximum number of IOPS that can be performed per second by background tasks in an emergency. The default value is `2000`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_thread_concurrency	Specifies the maximum number of threads allowed internally for the InnoDB storage engine. The default value is `0`, which indicates that no limit is set. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_thread_sleep_delay	Specifies the time in microseconds that an InnoDB thread sleeps before being added to the InnoDB wait queue. The default value is `10000`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
innodb_adaptive_hash_index_parts	Specifies the number of partitions in the adaptive hash index search system. The default value is `8`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but cannot set it.
innodb_numa_interleave	Specifies whether to enable the NUMA interleaving memory allocation strategy for the buffer pool. The default value is `OFF`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but cannot set it.
innodb_open_files	Specifies the maximum number of files that can be opened at a time. The default value is `2000`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but cannot set it.
innodb_page_cleaners	Specifies the number of threads for flushing dirty pages from the buffer pool. The default value is `1`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but cannot set it.
innodb_purge_threads	Specifies the number of background threads for purge operations. The default value is `4`. Note This variable is provided only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but cannot set it.
innodb_read_io_threads	The number of I/O threads for read operations. The default value is `4`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_sync_array_size	The size of the mutex/lock wait array. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_use_native_aio	Whether to use the Linux asynchronous I/O subsystem. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_write_io_threads	The number of I/O threads for write operations. The default value is `4`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_api_enable_binlog	Whether to allow the use of the InnoDB memcached plugin with MySQL binlogs. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_locks_unsafe_for_binlog	This variable affects how InnoDB uses gap locks for searches and index scans. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_log_buffer_size	The size of the InnoDB transaction log buffer, in bytes. The default value is `16777216`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_log_files_in_group	The number of log files in a log group. The default value is `2`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_log_file_size	The size of each log file in a log group, in bytes. The default value is `50331648`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_log_group_home_dir	The directory path for InnoDB redo logs. The default value is `./`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_undo_directory	The directory for the undo tablespaces created by InnoDB. The default value is `./`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_undo_tablespaces	The number of undo tablespaces available to InnoDB. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
default_tmp_storage_engine	The default temporary table storage engine. The default value is `InnoDB`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set the variable. However, the setting does not take effect.
innodb_tmpdir	The directory for storing temporary files for InnoDB. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set the variable. However, the setting does not take effect.
mecab_rc_file	The path to the MeCab configuration file. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_temp_data_file_path	The storage path for temporary data files for InnoDB. The default value is `ibtmp1:12M:autoextend`, which indicates that InnoDB will use a temporary data file named ibtmp1 with an initial size of 12 MB that automatically extends as needed to store additional temporary data. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_data_file_path	The storage path and filename for InnoDB data files. The default value is `ibdata1:12M:autoextend`, which indicates that InnoDB will use a temporary data file named ibtmp1 with an initial size of 12 MB that automatically extends as needed to store additional temporary data. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query the variable but cannot set it.
innodb_data_home_dir	The root directory for InnoDB data files. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
delayed_insert_limit	The maximum number of insert operations that can be performed using the INSERT DELAYED option. The default value is `100`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. The setting does not take effect but does not return an error.
delayed_insert_timeout	The maximum time that a delayed insert operation can be delayed. The default value is `300`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. The setting does not take effect but does not return an error.
delayed_queue_size	The size of the delayed insert queue. The default value is `1000`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. The setting does not take effect but does not return an error.
eq_range_index_dive_limit	The maximum number of rows that the optimizer can scan when it performs an index dive for an equality range query. The default value is `200`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. The setting does not take effect but does not return an error.
innodb_stats_auto_recalc	The option to enable or disable automatic recalculation. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. The setting does not take effect but does not return an error.

Variable	Description
max_tmp_tables	Specifies the maximum number of temporary tables that a user session can hold simultaneously. The default value is `32`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.

Variable	Description
ob_compatibility_mode	Specifies the compatibility mode of a tenant.
ob_route_policy	Specifies the routing strategy for selecting data replicas within an OBServer node.
performance_schema	Specifies whether to support queries for Performance information. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 8.0. The related feature is not supported. You can query and set this variable, but the setting has no effect.
resource_manager_plan	Activates the resource management plan. Different plans use different CPU quotas to limit user activities in resource groups.
license	Displays the type of license.
server_uuid	Displays the UUID of an OBServer node.
default_storage_engine	Displays the default storage engine of an OBServer node.

Variable	Description
datadir	Displays the local disk path for storing data.
plugin_dir	Displays the path for storing plugin DLLs.
secure_file_priv	Specifies the path that can be accessed when importing or exporting files.
ob_enable_hash_group_by	Specifies whether to enable the Hash Group by feature.

Variable	Description
skip_external_locking	Specifies whether to disable the external locking mechanism for MyISAM tables. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
myisam_mmap_size	Specifies the maximum memory size for memory-mapping compressed MyISAM files. The default value is `18446744073709551615`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.

Variable	Description
ob_sql_work_area_percentage	Specifies the percentage of tenant memory for SQL execution.
ob_sql_audit_percentage	Specifies the percentage of tenant memory for SQL audit.
ob_reserved_meta_memory_percentage	Specifies the percentage of reserved memory for a tenant, mainly for storing Meta-related structure information.
ob_temp_tablespace_size_percentage	Specifies the percentage of temporary table space size in the tenant disk.
range_alloc_block_size	Specifies the size of the block allocated for range optimization. The default value is `4096` bytes. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.

Variable name	Description
ndb_allow_copying_alter_table	Specifies whether to allow the `ALTER TABLE` statement and other DDL statements to use the copy operation for a table. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_autoincrement_prefetch_sz	Specifies the number of auto-increment values to be prefetched. This value can affect the performance and concurrent access capability of auto-increment columns. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_blob_read_batch_bytes	Specifies the size of BLOB data to be read in batches in an NDB cluster, in bytes. The default value is `65536`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_blob_write_batch_bytes	Specifies the size of BLOB data to be written in batches in an NDB cluster, in bytes. The default value is `65536`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_cache_check_time	Specifies the interval in milliseconds at which to check whether the cache needs to be refreshed on each NDB node. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_clear_apply_status	Specifies whether to clear the application status. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_data_node_neighbour	Defines the neighbor relationships of data nodes. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_default_column_format	Defines the default column format for a table, which can be fixed-length or variable-length. The default value is `FIXED`, indicating fixed-length storage. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_deferred_constraints	Specifies whether to defer constraint checks for a table. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_distribution	Specifies the default distribution method for an NDB table, which can be partitioned by hash key or linear hash. The default value is `KEYHASH`, indicating hash key partitioning. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_eventbuffer_free_percent	Specifies the percentage of free space in the event buffer of an NDB cluster. The default value is `20`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_eventbuffer_max_alloc	Specifies the maximum size of memory that can be allocated for the event buffer, in bytes. The default value is `0`, indicating no limit. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_extra_logging	Specifies whether to record information about the NDB storage engine in the MySQL error log. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_force_send	Specifies whether to immediately send the cache to NDB without waiting for other threads. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_fully_replicated	Specifies whether to fully replicate a new table. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect and no error will be returned.
ndb_index_stat_enable	Specifies whether to enable the NDB index statistics collection feature. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_index_stat_option	Specifies the options for generating NDB index statistics. The default value is `loop_checkon=1000ms,loop_idle=1000ms,loop_busy=100ms,update_batch=1,read_batch=4,idle_batch=32,check_batch=32,check_delay=1m,delete_batch=8,clean_delay=0,error_batch=4,error_delay=1m,evict_batch=8,evict_delay=1m,cache_limit=32M,cache_lowpct=90`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_join_pushdown	Specifies whether to enable the join pushdown optimization feature in the storage engine. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_binlog_index	Specifies whether to insert the mapping of epochs to binlog positions into the ndb_binlog_index table. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_empty_epochs	Specifies whether to write unchanged epoch transactions to the binlog. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_empty_update	Specifies whether to write unchanged update transactions to the binlog. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_exclusive_reads	Specifies whether to use an exclusive lock to record primary key reads. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_update_as_write	Specifies whether to write updates to the binlog as updates (OFF) or writes (ON). The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_update_minimal	Specifies the logging behavior of NDB Cluster. If the value is `ON`, NDB Cluster records only the minimal information of update operations. If the value is `OFF`, NDB Cluster records the changes of the entire row. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_log_updated_only	Specifies whether to write only the updated rows or the entire rows to the binlog when Mysqld writes updates to the binlog. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_optimization_delay	Specifies the wait time between groups of rows when you execute the OPTIMIZE TABLE statement on an NDB table. The unit is microseconds. The default value is `10`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_read_backup	Specifies whether to allow reading data from any fragment of any NDB table created later. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_recv_thread_activation_threshold	Specifies the activation threshold for receive threads. The default value is `8`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_recv_thread_cpu_mask	Specifies the CPU mask for receive threads. The default value is an empty string. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_report_thresh_binlog_epoch_slip	Specifies the maximum allowed size of a binlog timestamp jump before a report is generated. The default value is `10`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting has no effect.
ndb_report_thresh_binlog_mem_usage	Specifies the percentage threshold of the remaining available memory for binlog before sending a report. When the remaining available memory for binlog is less than this value, the system will send a report. The default value is `10`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndb_row_checksum	Specifies the checksum value for table rows. When the value is `1`, the checksum values for each row of data are calculated and saved. When the value is `0`, no checksum check is performed on the data of table rows. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndb_show_foreign_key_mock_tables	Specifies whether to display the mock tables for foreign key dependencies. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndb_slave_conflict_role	Specifies the role of the node in a circular replication (master-master) setup. The default value is `NONE`, indicating that the role is undefined or not configured. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndb_use_exact_count	Specifies whether to force NDB to use record counts to accelerate `SELECT count(*)` queries. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndb_use_transactions	Controls whether to enable NDB transaction support. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndbinfo_max_bytes	For testing and debugging only. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndbinfo_max_rows	For testing and debugging only. The default value is `10`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndbinfo_offline	Specifies whether to set the `ndbinfo` database to offline mode. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
ndbinfo_show_hidden	Specifies whether to display the underlying internal tables of the `ndbinfo` database in the MySQL client. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting will not take effect.
server_id_bits	Specifies the number of least significant bits in the 32-bit server_id that actually identify the server. The default value is `32`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndbinfo_database	Specifies the database for NDB information. The default value is `ndbinfo`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndbinfo_table_prefix	Specifies the prefix for NDB information tables. The default value is `ndb$`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndbinfo_version	Specifies the version of NDB information tables. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndb_batch_size	Specifies the batch size for NDB. The default value is `32768`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndb_cluster_connection_pool	Specifies the connection pool size for the NDB cluster. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndb_cluster_connection_pool_nodeids	Specifies the IDs of the NDB nodes to connect to. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndb_log_apply_status	Specifies the status of NDB log application. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
ndb_log_bin	Specifies whether to enable binary logging for NDB. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_log_fail_terminate	Specifies whether to terminate operations when a log failure occurs. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_log_orig	Specifies whether to retain original log data. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_log_transaction_id	Specifies whether to record transaction IDs in NDB logs. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_optimized_node_selection	Specifies whether to enable optimized transaction node selection. The default value is `3`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
Ndb_system_name	Specifies the name of the NDB system. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_use_copying_alter_table	Specifies whether to use copy-based ALTER TABLE operations in NDB. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_version	Specifies the version of the NDB storage engine. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_version_string	Specifies the version string of the NDB storage engine. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_wait_connected	Specifies whether to block and wait for a connection. The default value is `30`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_wait_setup	Specifies whether to block and wait for NDB setup. The default value is `30`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.
ndb_batch_size	Specifies the batch size for NDB. The default value is `32768`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable but cannot set it.

Variable name	Description
activate_all_roles_on_login	Specifies whether to automatically enable all roles upon login.
automatic_sp_privileges	Specifies whether to automatically grant ALTER and EXECUTE privileges to stored procedures.

Variable name	Description
innodb_ft_enable_diag_print	Enables or disables diagnostic output for InnoDB full-text indexes. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable, but the settings will not take effect.
innodb_ft_num_word_optimize	Specifies the minimum number of words to optimize during an OPTIMIZE TABLE operation. The default value is `2000`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable, but the settings will not take effect.
innodb_ft_result_cache_limit	Specifies the size of the InnoDB full-text index result cache. The default value is `2000000000` bytes. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable, but the settings will not take effect.
innodb_ft_server_stopword_table	Specifies the server stopword table for InnoDB full-text indexes. The default value is `NULL`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable, but the settings will not take effect.
innodb_optimize_fulltext_only	Controls the behavior of the OPTIMIZE TABLE statement on InnoDB tables with FULLTEXT indexes. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set this variable, but the settings will not take effect.
innodb_ft_cache_size	Specifies the size of the InnoDB full-text index cache. The default value is `8000000` bytes. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable, but you cannot set it.
innodb_ft_sort_pll_degree	Specifies the number of parallel threads for full-text index sorting. The default value is `2`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable, but you cannot set it.
innodb_ft_total_cache_size	Specifies the total cache size for InnoDB full-text indexes. The default value is `640000000` bytes. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable, but you cannot set it.
ft_stopword_file	Specifies the file path for stopword processing. The default value is `built-in`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query this variable, but you cannot set it.

Variable name	Description
runtime_filter_type	Specifies the type of Runtime Filter at the tenant level.
runtime_filter_wait_time_ms	Specifies the maximum wait time for a Runtime Filter.
runtime_filter_max_in_num	Specifies the number of distinct values (NDV) for a Runtime In Filter.
runtime_bloom_filter_max_size	Specifies the maximum memory usage for a Runtime Bloom Filter, in bytes.

Variable name	Description
lc_time_names	Controls the language for displaying date and month names and abbreviations.
time_zone	Sets the time zone for the current tenant session. It supports the Offset format `'+08:00'` and the region format `Asia/Shanghai`.
system_time_zone	Sets the system time zone of the server machine.
error_on_overlap_time	Specifies whether to return an error when ambiguous time zones occur in the daylight saving time overlap period.
nls_territory	Specifies the current region in database internationalization support. It is used with `nls_language`.
nls_date_language	Specifies the default date language in database internationalization support.
nls_calendar	Controls the calendar system used by the database.
ob_timestamp_service	Specifies the timestamp service to use.
default_week_format	Sets the default mode value of the WEEK() function for calculating the day of the week. The default value is `0`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the setting has no effect.
show_old_temporals	Controls whether to display the old timestamp columns. The default value is `OFF`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the setting has no effect.
date_format	Sets the default date format. The default value is `%Y-%m-%d`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query this variable but cannot set it.
datetime_format	Sets the default date and time format. The default value is `%Y-%m-%d %H:%i:%s`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query this variable but cannot set it.
language	Sets the language used by MySQL. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query this variable but cannot set it.
lc_messages_dir	Sets the language used for error messages. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query this variable but cannot set it.

Variable name	Description
updatable_views_with_limit	Controls whether to allow UPDATE or DELETE operations on views with the LIMIT clause. The default value is `1`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable, but the setting has no effect.

Variable name	Description
autocommit	Specifies whether to automatically commit transactions.
tx_isolation	Specifies the transaction isolation level.
ob_proxy_set_trx_executed	Specifies whether to send the `START TRANSACTION Syntax` statement to an OBServer through an ODP.
ob_early_lock_release	Specifies whether to enable early lock release (ELR) for a transaction. Note This variable is deprecated starting from V2.2.30. ELR behavior is now controlled by the tenant-level parameter `enable_early_lock_release`.
ob_trx_idle_timeout	Specifies the transaction idle timeout. A transaction is considered idle if the execution interval between two statements exceeds the specified value.
transaction_isolation	Specifies the transaction isolation level.
transaction_read_only	Specifies whether to allow only read-only transactions.
ob_trx_lock_timeout	Specifies the transaction lock timeout.
tx_read_only	Specifies whether to allow only read-only transactions.
ob_trx_timeout	Specifies the transaction timeout.
gtid_executed	Stores all committed transactions and GTIDs set by statements. The default value is `NULL`. Note This variable is for MySQL 5.7 compatibility. You can query this variable, but cannot set it.
gtid_owned	Stores the list of all GTIDs in use and the thread IDs of the threads that own them. The default value is `NULL`. Note This variable is for MySQL 5.7 compatibility. You can query this variable, but cannot set it.
completion_type	Specifies the transaction type to be selected when a statement is completed. The default value is `NO_CHAIN`. Note This variable is for MySQL 5.7 compatibility. You can query and set this variable. However, the settings do not take effect.
transaction_alloc_block_size	Specifies the initial memory block size allocated to each transaction. The default value is `8192`. Note This variable is for MySQL 5.7 compatibility. You can query and set this variable. However, the settings do not take effect.
transaction_prealloc_size	Specifies the preallocated memory block size for each transaction. The default value is `4069`. Note This variable is for MySQL 5.7 compatibility. You can query and set this variable. However, the settings do not take effect.
transaction_write_set_extraction	Specifies the algorithm type for generating identifiers for write operations related to transactions. The default value is `OFF`. Note This variable is for MySQL 5.7 compatibility. You can query and set this variable. However, the settings do not take effect.

Variable name	Description
ob_enable_sql_audit	Specifies whether to enable SQL Audit for the current tenant.

Variable name	Description
avoid_temporal_upgrade	Manages the upgrade behavior of temporal data (such as dates and times). The default value is `OFF`. Note This variable is for MySQL 5.7 compatibility. You can query and set this variable. However, the settings do not take effect.

Variable name	Description
nls_length_semantics	Specifies the length semantics of the CHAR and VARCHAR2 data types.
nls_nchar_conv_excp	Specifies whether to return an error when data is lost during conversion between NCHAR/NVARCHAR2 and CHAR/VARCHAR2.
nls_numeric_characters	Specifies the decimal separator and thousand separator for strings during conversion between numbers and strings.
nls_currency	Specifies the local currency symbol for the `L` element in the number format.
nls_iso_currency	Specifies the local currency symbol for the `C` element in the number format.
nls_dual_currency	Specifies the local currency symbol for the `U` element in the number format.
nls_date_format	Specifies the format for converting a date to a string and for implicitly converting a string to a date.
nls_timestamp_format	Specifies the format for converting a TIMESTAMP or TIMESTAMP_LTZ value to a string and for implicitly converting a string to a TIMESTAMP or TIMESTAMP_LTZ value.
nls_timestamp_tz_format	Specifies the format for converting a TIMESTAMP_TZ value to a string and for implicitly converting a string to a TIMESTAMP_TZ value.
explicit_defaults_for_timestamp	Specifies whether to enable nonstandard behavior for the TIMESTAMP data type when handling default values and NULL values.
log_row_value_options	Specifies whether to enable partial updates for LOBs.
ob_default_lob_inrow_threshold	Specifies the default in-row storage threshold for LOB fields when creating a table.

Variable	Description
connect_timeout	Specifies the connection timeout.
ob_pl_block_timeout	Specifies the maximum timeout for PL.
cursor_sharing	Specifies whether to parameterize SQL statements.
profiling	Enables or disables statement analysis. The default value is `0`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect.
profiling_history_size	Specifies the number of query performance records to be saved. The default value is `15`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect.
have_profiling	Specifies whether query performance analysis is supported. The default value is `NO`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query this variable, but cannot set it.
innodb_strict_mode	Specifies the SQL check mode for specific syntax.
max_connections	Specifies the maximum number of connections for the entire tenant.
sql_mode	Specifies the SQL mode. Different SQL modes have a significant impact on behaviors such as insertions.
sql_quote_show_create	Specifies whether to enable identifier quoting for the `SHOW CREATE TABLE` and `SHOW CREATE DATABASE` statements.
sql_throttle_current_priority	Specifies the throttling priority. Requests on sessions where `sql_throttle_current_priority` is less than `sql_throttle_priority` are throttled.
sql_throttle_priority	Specifies the throttling priority.
sql_throttle_rt	Specifies the RT value.
max_allowed_packet	Specifies the maximum size of a network packet.
max_user_connections	Specifies the maximum number of connections that a single user can establish with an OBServer node. A value of `0` indicates no limit.
max_sp_recursion_depth	Specifies the maximum number of recursive calls allowed for any specified stored procedure.
sql_select_limit	Specifies the maximum number of rows that a SELECT query can return.
max_connections	Specifies the maximum number of connections for the entire tenant.
ob_enable_blk_nestedloop_join	Specifies whether to allow block nested loop joins.
parallel_max_servers	Specifies the maximum number of threads in the parallel execution (PX) thread pool on each server.
innodb_stats_persistent	Specifies whether to persist InnoDB index statistics to disk.
ob_enable_parameter_anonymous_block	Specifies whether to enable the anonymous block parameterization feature globally.
parser_max_mem_size	Specifies the maximum amount of memory available for the parser. The default value is `18446744073709551615`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect.

Variable	Description
innodb_deadlock_detect	Specifies whether to disable deadlock detection. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_lock_wait_timeout	Specifies the maximum time (in seconds) that an InnoDB transaction waits for a lock. The default value is `50`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_print_all_deadlocks	Specifies whether to record all InnoDB deadlock information of user transactions in the error log. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_table_locks	Specifies the behavior of InnoDB table-level locking. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
max_write_lock_count	Limits the number of write locks that can be obtained to prevent excessive lock resource consumption in high-concurrency write scenarios. The default value is `18446744073709551615`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
metadata_locks_cache_size	Specifies the size of the metadata lock cache. The default value is `1024` (in bytes). Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
metadata_locks_hash_instances	Specifies the number of instances of the metadata lock hash table. The default value is `8`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.

Variable	Description
innodb_stats_include_delete_marked	Specifies whether to include rows marked for deletion in statistics calculations. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_method	Specifies the method for calculating InnoDB statistics. The default value is `nulls_equal`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_on_metadata	Controls the method for retrieving table and column statistics from INFORMATION_SCHEMA. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_persistent	Specifies whether to persist statistics. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_persistent_sample_pages	Specifies the number of sample pages for persistent statistics. The default value is `20`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_sample_pages	Specifies the number of sample pages for InnoDB statistics. The default value is `8`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
innodb_stats_transient_sample_pages	Specifies the number of sample pages for transient statistics. The default value is `8`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable name	Description
binlog_row_image	Specifies whether to record full-column logs.
ob_log_level	Specifies the log level for the session. If not specified, the system log level is used.
tracefile_identifier	Specifies the content to be added to the log for filtering row iteration tracking logs.
master_verify_checksum	Specifies whether to enable checksum verification. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_cache_size	Specifies the size of the transaction cache. The unit is bytes. The default value is `32768`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_direct_non_transactional_updates	If this variable is enabled, updates to non-transactional tables are directly written to the binlog instead of the transaction cache. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_error_action	Specifies the server behavior when an error occurs. The default value is `ABORT_SERVER`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_group_commit_sync_delay	Specifies the time to wait after binlog submission before synchronizing the binlog file to disk. The unit is microseconds. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_group_commit_sync_no_delay_count	Specifies the maximum number of delayed transactions to wait for. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_max_flush_queue_time	This variable has no effect on the system. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_order_commits	If this variable is enabled on the source server, transaction commit instructions are serialized on a single thread. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_stmt_cache_size	Specifies the binlog cache size for non-transactional statements issued during a transaction. The default value is `32768`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_transaction_dependency_history_size	Specifies the maximum number of row hashes stored in memory for finding the last transaction that modified a specified row. The default value is `25000`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
binlog_transaction_dependency_tracking	Specifies the source of dependency information. The source uses this information to determine which transactions can be executed in parallel by the multithreaded applications of the replica. The default value is `COMMIT_ORDER`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
expire_logs_days	Specifies the retention period of binlog files. The unit is days. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
log_bin_trust_function_creators	Specifies whether to trust that the creators of stored functions will not create stored functions that cause unsafe events to be written to the binlog. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
log_bin_use_v1_row_events	Specifies whether to use binlog version 2. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
log_builtin_as_identified_by_password	This variable affects the binlog of user management statements. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
max_binlog_cache_size	This variable specifies the maximum cache size that can be used for binlogs, in bytes. If the number of bytes required for a transaction exceeds the value specified by this variable, an error is returned indicating that the transaction requires more than `max_binlog_cache_size` bytes of storage. The default value is `18446744073709500416`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
max_binlog_size	This variable specifies the maximum size of a binlog file, in bytes. If the size of the current binlog file exceeds the value specified by this variable, the server automatically closes the current binlog file and creates a new binlog file to continue recording subsequent database operations. The default value is `1073741824`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
max_binlog_stmt_cache_size	This variable specifies the cache size required for non-transactional statements executed within a transaction, in bytes. The default value is `18446744073709547520`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
sync_binlog	This variable specifies how frequently the server synchronizes binlogs to the disk. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
binlog_direct_non_transactional_updates	When this variable is enabled, updates to non-transactional tables are directly written to the binlog instead of being cached in the transaction cache. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
log_statements_unsafe_for_binlog	Specifies whether to record error code 1592 information to the error log. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect and no error is returned.
binlog_gtid_simple_recovery	This variable specifies how the server iterates through binlog files when searching for GTIDs during startup or restart. The default value is `1`, which means that the values of `gtid_executed` and `gtid_purged` are calculated based on the values of `previous_gtids_log_event` in the latest and oldest binlog files at startup. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
log_bin_basename	The full path name of the binlog file. The default value is `null`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
log_bin_index	The name and path of the binlog index file. The default value is `null`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
log_slave_updates	Specifies whether the replica server records updates received from the primary server's binlog to its own binlog. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.

Variable name	Description
join_buffer_size	The minimum size of the buffer used for pure index scans, range index scans, and full table scans without using an index. The unit is bytes, and the default value is `262144`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
max_join_size	The maximum number of rows allowed in a JOIN operation. The default value is `18446744073709547520`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
max_length_for_sort_data	The truncation value for index values, used to determine which file sort algorithm to use. The default value is `1024`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
max_prepared_stmt_count	The maximum number of prepared statements allowed on the server. The default value is `16382`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
max_sort_length	The number of bytes used for sorting numeric values. The default value is `1024`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
min_examined_row_limit	The minimum number of rows that must be examined to be recorded in the slow query log. Queries that examine fewer rows than this variable specifies will not be recorded in the slow query log. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
multi_range_count	The maximum number of Range ranges allowed in a query statement. The default value is `256`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
query_alloc_block_size	The size of memory blocks allocated for objects created during statement parsing and execution. The unit is bytes, and the default value is `8192`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
query_prealloc_size	The size of the fixed buffer used for statement parsing and execution. The unit is bytes, and the default value is `8192`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
slow_query_log	Controls whether to enable the slow query log. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
slow_query_log_file	Specifies the filename for the slow query log. The default value is `/usr/local/mysql/data/obrd-slow.log`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
sort_buffer_size	The size of the buffer used for sorting. The unit is bytes, and the default value is `262144`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
sql_buffer_result	Controls whether to store the results of `SELECT` statements in a temporary table. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
flush	Controls whether to persist SQL statement modifications to disk. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
flush_time	Controls the automatic refresh of all tables to disk at specified intervals in seconds. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
myisam_data_pointer_size	The default pointer size for MyISAM tables created without the `MAX_ROWS` option specified. The unit is bytes, and the default value is `6`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not produce an error but has no effect.
myisam_max_sort_file_size	The maximum size of a temporary file that can be used when rebuilding a MyISAM index during `REPAIR TABLE`, `ALTER TABLE`, or `LOAD DATA` operations. The unit is bytes. The default value is `9223372036853720064`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
myisam_repair_threads	The number of concurrent threads for repairing a MyISAM table. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
myisam_sort_buffer_size	The size of the buffer allocated for sorting MyISAM indexes during `REPAIR TABLE` operations or for creating indexes using `CREATE INDEX` (or `ALTER TABLE`). The unit is bytes. The default value is `8388608`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
myisam_stats_method	The method used by the server to calculate NULL values when collecting statistics about the distribution of index values in MyISAM tables. The default value is `nulls_unequal`, which treats NULL values as regular values. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
myisam_use_mmap	Whether to use memory mapping for reading and writing MyISAM tables. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
preload_buffer_size	The size of the buffer used for preloading indexes. The unit is bytes. The default value is `32768`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
read_buffer_size	The size of the buffer available for reading data. The unit is bytes. The default value is `131072`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
read_rnd_buffer_size	The size of the buffer used for reading data from MyISAM tables and for optimizing multi-range reads for any storage engine. The unit is bytes. The default value is `262144`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
sync_frm	Whether to synchronize the metadata of InnoDB tables to the `.frm` files on the disk. The default value is `1`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
table_open_cache	The maximum number of tables that can be opened simultaneously by all threads. The default value is `2000`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
internal_tmp_disk_storage_engine	The storage engine for internal temporary tables on disk. The default value is `INNODB`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
keep_files_on_create	When the `DATA DIRECTORY` or `INDEX DIRECTORY` option is not used to specify the location of data files or index files, this variable controls whether the server retains existing files in the corresponding directory when creating a MyISAM table. The default value is `OFF`, which means existing files will be overwritten. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
max_heap_table_size	The maximum size to which a user-created memory table can grow. The unit is bytes. The default value is `16777216`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
bulk_insert_buffer_size	The size of the buffer used for bulk inserts. The unit is bytes per thread. The default value is `8388608`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
general_log_file	The name of the general query log file. The default format is `host_name.log`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect.
host_cache_size	The size of the host cache. The default value is `279`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_error_verbosity	The level of detail for writing error, warning, and comment information to the error log. The default value is `3`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_output	The output destination for general query logs and slow query logs. The default value is `FILE`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_queries_not_using_indexes	Whether to record queries that do not use indexes to the slow query log. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_slow_admin_statements	Whether to record slow administrative statements such as ALTER TABLE, ANALYZE TABLE, CHECK TABLE, CREATE INDEX, DROP INDEX, OPTIMIZE TABLE, and REPAIR TABLE to the slow query log. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_syslog	Whether to record error logs to the system log. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_syslog_facility	The tool for writing error logs to the system log. The default value is `daemon`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_syslog_include_pid	Whether to write the service process ID in the error log output to the system log. The default value is `1`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_syslog_tag	The tag to be added to the server identifier in the error log output written to the system log. The default value is `null`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_throttle_queries_not_using_indexes	The maximum number of statements to be written to the slow query log per minute. The default value is `0`, indicating no limit. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_timestamps	The timezone for the timestamps of error logs, general logs, and slow query logs written to files. The default value is `UTC`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
log_warnings	The level of additional warning information to be recorded to the error log. The default value is `2`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
max_delayed_threads	The maximum number of threads that can be created to process INSERT DELAYED statements. The default value is `20`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
offline_mode	Whether to set the server to offline mode. The default value is `0`, indicating that the server is not set to offline mode. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
require_secure_transport	Whether to use a secure transport for the connection between the client and the server. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
slow_launch_time	The threshold for the time taken to create a thread. If the time exceeds this threshold, the value of the Slow_launch_threads status variable increases. The unit is seconds. The default value is `2`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
sql_log_off	Specifies whether to enable (OFF) or disable (ON) the general query log for the current session. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
thread_cache_size	The maximum number of threads that can be cached in the thread cache. The default value is `9`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
thread_pool_high_priority_connection	Specifies whether to reserve idle threads for high-priority connections in the thread pool. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
thread_pool_max_unused_threads	The maximum number of unused threads in the thread pool. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
thread_pool_prio_kickup_timer	The time in milliseconds that a statement must wait before it is moved to the high-priority queue. The default value is `1000`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
thread_pool_stall_limit	The maximum time in 10 milliseconds that a statement must complete after it starts executing. The default value is `6`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, the setting does not take effect.
have_statement_timeout	Specifies whether to enable the statement timeout feature. The default value is `ON`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
old	A compatibility variable used to resolve compatibility issues. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
version_tokens_session_number	An internal variable. The default value is `0`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
back_log	The maximum number of connection requests that can be saved in the waiting connection request queue while the server is processing connection requests. The default value is `80`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
basedir	The path name of the installation root directory. The default value is `/usr/local/mysql/`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
bind_address	The IP address to which the server binds when listening for TCP/IP client connections. The default value is `*`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
core_file	Specifies whether to generate a core file before the server exits when a fatal error occurs. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
have_compress	Specifies whether the zlib compression library required for the COMPRESS() and UNCOMPRESS() functions is available. The default value is `ON`, indicating that the library is available. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
ignore_db_dirs	A comma-separated list of names that are not considered database directories in the data directory. The default value is `null`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
init_file	The name of a file that contains SQL statements to be executed when the server starts. The default value is `null`. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
large_files_support	Specifies whether the server supports processing large files. The default value is `1`, indicating that the server supports processing large files. Note This variable is for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
large_pages	Specifies whether to enable the large page feature. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
large_page_size	If the large page feature is enabled, this variable specifies the size of the memory page, in bytes. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
locked_in_memory	Indicates whether the server is locked in memory. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
log_error	The output destination of the error log file. The default value is `./obrd.16c.vd3-s2h6-n3.err`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
named_pipe	Indicates whether the server allows clients to connect by using named pipes. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
named_pipe_full_access_group	If the server allows clients to connect by using named pipes, this variable specifies the Windows user group that has permission to use named pipes. The default value is `empty string`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
open_files_limit	The number of file descriptors available to the server. The default value is `655360`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
shared_memory	Indicates whether the server allows clients to connect by using shared memory. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
shared_memory_base_name	The name of the shared memory used for shared memory connections. The default value is `MYSQL`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
skip_name_resolve	Specifies whether to resolve hostnames when checking client connections. The default value is `OFF`, which indicates that hostnames must be resolved. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
skip_networking	Specifies whether to allow TCP/IP connections. The default value is `OFF`, which indicates that TCP/IP connections are disabled. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
thread_handling	The thread model used by the server to handle client connections. The default value is `one-thread-per-connection`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
thread_pool_algorithm	The algorithm used by the thread pool plugin. The default value is `0`, which indicates the conservative low-concurrency algorithm. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
thread_pool_size	The number of thread groups in the thread pool. The default value is `16`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
thread_stack	The stack size of each thread. The default value is `262144`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.
tls_version	The protocols that the server allows for encrypted connections. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported, so you can query this variable but cannot set it.

Variable name	Description
mysqlx_connect_timeout	The time that the X plugin waits for the first data packet from a new client connection, in seconds. Default value: `30`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect.
mysqlx_idle_worker_thread_timeout	The time that an idle worker thread can remain idle before being terminated, in seconds. Default value: `60`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect.
mysqlx_max_allowed_packet	The maximum size of a network data packet that the X plugin can receive, in bytes. Default value: `67108864`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect.
mysqlx_max_connections	The maximum number of concurrent client connections that the X plugin can accept. Default value: `100`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect.
mysqlx_min_worker_threads	The minimum number of worker threads that the X plugin uses to process client requests. Default value: `2`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting will not take effect.
mysqlx_bind_address	The network address where the X plugin listens for TCP/IP connections. The default value is `*`, which indicates that the X plugin accepts TCP/IP connections from all server hosts. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_port	The network port where the X plugin listens for TCP/IP connections. The default value is `33060`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_port_open_timeout	The time that the X plugin waits for a TCP/IP port to be idle, in seconds. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_socket	The path of the Unix socket file used by the X plugin for connections. The default value is `/tmp/mysqlx.sock`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_ca	The path name of the SSL certificate authority (CA) file used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_capath	The directory path of the SSL certificate authority (CA) certificate files used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_cert	The path name of the SSL certificate file used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_cipher	The list of encryption algorithms used for SSL encryption by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_crl	The file name of the certificate revocation list (CRL) file used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_crlpath	The directory path of the certificate revocation list (CRL) file used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.
mysqlx_ssl_key	The path name of the SSL certificate key file used by the X plugin. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable, but you cannot set it.

Variable name	Description
performance_schema_show_processlist	This variable specifies the implementation of SHOW PROCESSLIST. The default value is `0`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
performance_schema_accounts_size	This variable specifies the number of rows in the `accounts` table. The default value is `-1`, indicating automatic scaling. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_digests_size	This variable specifies the maximum number of rows in the `events_statements_summary_by_digest` table. The default value is `10000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_stages_history_long_size	This variable specifies the number of rows in the `events_stages_history_long` table. The default value is `10000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_stages_history_size	This variable specifies the number of rows per thread in the `events_stages_history` table. The default value is `10`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_statements_history_long_size	This variable specifies the number of rows in the `events_statements_history_long` table. The default value is `10000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_statements_history_size	This variable specifies the number of rows per thread in the `events_statements_history` table. The default value is `10`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_transactions_history_long_size	This variable specifies the number of rows in the `events_transactions_history_long` table. The default value is `10000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_transactions_history_size	This variable specifies the number of rows per thread in the `events_transactions_history` table. The default value is `10`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_waits_history_long_size	This variable specifies the number of rows in the `events_waits_history_long` table. The default value is `10000`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_events_waits_history_size	This variable specifies the number of rows per thread in the `events_waits_history` table. The default value is `10`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_hosts_size	This variable specifies the number of rows in the `hosts` table. The default value is `-1`, indicating automatic scaling. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_max_cond_classes	This variable specifies the maximum number of condition collectors. The default value is `80`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_max_cond_instances	This variable specifies the maximum number of condition objects to be collected. The default value is `-1`, indicating automatic scaling. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_max_digest_length	This variable specifies the maximum length of a normalized SQL statement in bytes when it is stored in the performance schema. The default value is `1024`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but cannot set it.
performance_schema_max_file_classes	Specifies the maximum number of file instruments. The default value is `80`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_file_handles	Specifies the maximum number of file handles. The default value is `32768`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_file_instances	Specifies the maximum number of file instances. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_index_stat	Specifies the maximum number of indexes in the statistics maintained by the Performance Schema. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_memory_classes	Specifies the maximum number of memory instruments. The default value is `320`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_metadata_locks	Specifies the maximum number of metadata lock instruments. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_mutex_classes	Specifies the maximum number of mutex instruments. The default value is `200`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_mutex_instances	Specifies the maximum number of mutex instances. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_prepared_statements_instances	Specifies the maximum number of rows in the `prepared_statements_instances` table. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_program_instances	Specifies the maximum number of stored programs in the statistics maintained by the Performance Schema. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_rwlock_classes	Specifies the maximum number of rwlock instruments. The default value is `50`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_rwlock_instances	Specifies the maximum number of rwlock instances. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_socket_classes	Specifies the maximum number of socket instruments. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_socket_instances	Specifies the maximum number of socket instances. The default value is `-1`, which indicates automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_sql_text_length	Specifies the maximum length of an SQL statement that can be stored in the `SQL_TEXT` column of the `events_statements_current`, `events_statements_history`, and `events_statements_history_long` tables, in bytes. The default value is `1024`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_stage_classes	Specifies the maximum number of stage instruments. The default value is `150`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_statement_classes	Specifies the maximum number of statement instruments. The default value is `193`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
performance_schema_max_statement_stack	The maximum depth of nested stored procedure calls in the statistics maintained by the Performance Schema. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_max_table_handles	The maximum number of table objects that can be opened. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_max_table_instances	The maximum number of table objects that can be collected. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_max_table_lock_stat	The maximum number of tables in the lock statistics maintained by the Performance Schema. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_max_thread_classes	The maximum number of thread collectors. The default value is `50`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_max_thread_instances	The maximum number of thread objects that can be collected. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_session_connect_attrs_size	The preallocated memory size in bytes for storing key-value pairs of connection attributes for each thread. The default value is `512`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_setup_actors_size	The number of rows in the `setup_actors` table. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_setup_objects_size	The number of rows in the `setup_objects` table. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.
performance_schema_users_size	The number of rows in the `users` table. The default value is `-1`, indicating automatic scaling. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported, so you can query this variable but cannot set it.

Variable name	Description
foreign_key_checks	Specifies whether to check foreign key constraints in DML/DDL operations.

Variable name	Description
optimizer_capture_sql_plan_baselines	Specifies whether to automatically capture new plans to the plan baseline.
optimizer_use_sql_plan_baselines	Specifies whether the optimizer uses the plan baseline.
parallel_degree_policy	Specifies the parallelism selection strategy.
parallel_degree_limit	Specifies the upper limit of the parallelism selected by the optimizer when the Auto DOP strategy is used.
parallel_min_scan_time_threshold	Specifies the minimum execution time for evaluating parallel processing of base table scans.
optimizer_dynamic_sampling	Specifies the level of dynamic sampling.
optimizer_features_enable	Enables the optimizer features of different OceanBase Database versions.
ob_enable_transformation	Specifies whether to enable the rewrite feature of the SQL optimizer.
range_index_dive_limit	Specifies the maximum number of ranges to use when the optimizer estimates rows based on the storage layer.
partition_index_dive_limit	Specifies the maximum number of partitions to use when the optimizer estimates rows based on the storage layer.

Variable name	Description
auto_increment_increment	Specifies the auto-increment step size. This variable is available only for MySQL clients.
auto_increment_offset	Specifies the starting value of the `AUTO_INCREMENT` column.
identity	`identity` and the `last_insert_id` variable are synonyms. You can execute the `select @@identity` statement to query the value.
sql_auto_is_null	Specifies whether to obtain the value of the auto-increment column of the last inserted row.
auto_increment_cache_size	Specifies the number of cached auto-increment values.
div_precision_increment	Specifies the increment of the precision of the result of a division operation based on the precision of the dividend. This is a MySQL-compatible feature.

Variable name	Description
character_set_client	The character set for statements sent by the client.
character_set_connection	The character set to which received statements should be converted.
character_set_database	The character set for the default database.
character_set_results	The character set to which result sets or error messages should be converted before being sent back to the client.
character_set_server	The character set for the server.
character_set_system	The character set used by the server.
collation_connection	The character set and collation for the connection.
collation_database	The default character set and collation for the database.
collation_server	The default character set and collation for the server.
character_set_filesystem	The character set type for the filesystem.
sql_warnings	Controls whether a single-line INSERT statement generates an information string when an alert occurs.
init_connect	The string to be executed by the server for each client connection. The string consists of one or more SQL statements separated by semicolons.
nls_sort	The collation for string values.
nls_comp	The comparison rule for string values.
nls_characterset	The default character set for data types such as CHAR, VARCHAR2, and CLOB in the database.
nls_nchar_characterset	The default character set for data types such as NCHAR, NVARCHAR2, and NCLOB.
default_collation_for_utf8mb4	The default collation for the utf8mb4 character set, which defaults to `utf8mb4_general_ci`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. Setting it does not cause an error, but the setting has no effect.
have_symlink	Whether to support symbolic links, default value is `YES`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query it.
character_sets_dir	The directory for character set files. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query it.

Variable name	Description
group_replication_allow_local_disjoint_gtids_join	Specifies whether to allow a server with local transactions not in the group to join the group. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_allow_local_lower_version_join	Specifies whether to allow a server with a lower MySQL Server version than other members to join the group. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_auto_increment_increment	Specifies the increment value for the auto-increment column of each member in the replication group. This ensures that the auto-increment column values are ordered and non-overlapping in a multi-primary group. The default value is `7`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_bootstrap_group	Specifies whether to use the current server to bootstrap the group. This variable can only be set on one server and only during the initial bootstrap or re-bootstrap. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_components_stop_timeout	Specifies the timeout for stopping each component when group replication is disabled, in seconds. The default value is `2`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_compression_threshold	Specifies the threshold for compressing messages between group members. When the threshold is exceeded, messages between group members are compressed. The default value is `1000000`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_enforce_update_everywhere_checks	Specifies whether to enable or disable strict consistency checks for multi-primary updates at any time. The default value is `OFF`, indicating that checks are disabled. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_exit_state_action	Specifies the behavior of group replication when a server instance leaves the group due to an exception. The default value is `READ_ONLY`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_flow_control_applier_threshold	Specifies the number of transactions waiting in the application queue that triggers flow control. The default value is `25000`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_flow_control_certifier_threshold	Specifies the number of transactions waiting in the certifier queue that triggers flow control. The default value is `25000`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_flow_control_mode	Specifies the mode for flow control. The default value is `QUOTA`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_force_members	Specifies the list of member addresses in the format `host1:port1,host2:port2`. This variable is used to force the creation of a new group. After setting it, excluded members (those not specified in this variable) will not receive new view messages and will be blocked (write operations will be blocked). The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_group_name	Specifies the name of the group replication group to which the current server belongs. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_group_seeds	Specifies the list of seed member addresses in the format `host1:port1,host2:port2`. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported, but you can query and set it. The setting will not take effect and will not return an error.
group_replication_gtid_assignment_block_size	The number of consecutive GTIDs to be reserved for each member. The default value is `1000000`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_ip_whitelist	The list of hosts (IP addresses or host names) that are allowed to connect to the group. These hosts are referred to as whitelist hosts. The default value is `AUTOMATIC`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_local_address	The network address for other members to connect to the group replication member. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_member_weight	The percentage weight of a member. This weight affects the chance of the member being selected as the primary node during a failover. This parameter is meaningful only for a group in single-primary mode. When the primary node of a group in single-primary mode leaves the group, the member with the highest weight is selected as the new primary node. The default value is `50`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_poll_spin_loops	The number of times the communication thread of group replication waits for the communication engine mutex to be released before waiting for more incoming network messages. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_complete_at	The strategy for applying cached transactions after the status transmission is completed in a distributed recovery. The default value is `TRANSACTIONS_APPLIED`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_reconnect_interval	The interval for reconnection attempts to find an available donor when a new server cannot find a donor for distributed recovery. The unit is seconds. The default value is `60`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_retry_count	The number of reconnection attempts to find an available donor when a new server cannot find a donor for distributed recovery. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_ca	The path to the file that contains the list of trusted SSL certificate authorities for distributed recovery connections. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_capath	The path to the directory that contains the certificates issued by trusted SSL certificate authorities for distributed recovery connections. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_cert	The name of the SSL certificate file for establishing a secure connection for distributed recovery. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_cipher	The list of allowed encryption algorithms for SSL encryption. The available encryption algorithms depend on the version of the SSL library used when MySQL Server is compiled. Different SSL libraries support different encryption algorithms. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_crl	The name of the file that contains the certificate revocation list. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_crlpath	The path to the directory that contains the certificate revocation list. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_key	The name of the SSL key file for establishing a secure connection for distributed recovery. The default value is empty. Note This variable is available only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect.
group_replication_recovery_ssl_verify_server_cert	Specifies whether to verify the server common name in the donor certificate during distributed recovery. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_recovery_use_ssl	Specifies whether to use SSL for the connection channel used in distributed recovery by group replication members. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_single_primary_mode	Specifies whether to run group replication in single-primary mode and automatically select a server to handle read/write workloads. If this variable is set to `ON`, only one readable/writable primary node exists, and all other group members are secondary nodes. If this variable is set to `OFF`, the single-primary mode is disabled, and the multi-primary mode is enabled. In the multi-primary mode, all group members are readable/writable primary nodes. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_ssl_mode	Specifies the security state of the SSL connection between group replication members. The default value is `DISABLED`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_start_on_boot	Specifies whether to start group replication when the server starts. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_transaction_size_limit	Specifies the maximum size of a transaction that can be received in group replication, in bytes. The default value is `150000000`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.
group_replication_unreachable_majority_timeout	Specifies the wait time before a group member leaves the group when it loses contact with the majority of other group members due to a network partition. The unit is seconds. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting has no effect.

Variable	Description
block_encryption_mode	Specifies the encryption algorithm used in the aes_encrypt and aes_decrypt functions.
net_retry_count	Specifies the number of network retries. The default value is `10`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
old_passwords	Specifies the password hashing method used by functions. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
disconnect_on_expired_password	Specifies whether to disconnect a session when the password expires. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
external_user	Specifies the external user that connects to MySQL. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
have_crypt	Specifies whether MySQL supports the crypt() function. The default value is `YES`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query this variable but cannot set it.
proxy_user	Specifies the proxy user for authentication. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
ob_enable_transmission_checksum	Specifies whether to enable packet checksum verification between OBProxy and OBServer nodes. The setting takes effect immediately.
ob_last_schema_version	Specifies the latest schema version used in the current session.
ob_proxy_global_variables_version	Specifies the latest version of global variables to be returned by OBServer nodes to OBProxy.
new	Specifies whether to enable certain behaviors of MySQL 4.1 in MySQL 4.0 and retain them for backward compatibility. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
version_tokens_session	Specifies the session-level version tag. The default value is `NULL`, which indicates that any server version list matches. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
plugin_load	Specifies the list of plugins to be loaded at startup. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
plugin_load_add	Specifies the plugins to be added at runtime. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
debug	Specifies the debug options. The default value is `d:t:i:o,/tmp/mysqld.trace`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
ob_global_debug_sync	Specifies a synchronization point for debugging. Setting this variable affects all sessions.

Variable name	Description
cte_max_recursion_depth	The maximum recursion depth of a common table expression (CTE). The server terminates the execution of any CTE that exceeds this value.
is_result_accurate	Indicates whether the query result is accurate when the `topk` hint is specified.
net_read_timeout	The number of seconds to wait for additional data before interrupting a read operation.
net_write_timeout	The number of seconds to wait for a block to be written to the connection before interrupting a write operation.
ob_enable_aggregation_pushdown	Specifies whether to allow aggregation pushdown.
ob_enable_index_direct_select	Specifies whether to allow direct queries on index tables.
ob_enable_jit	Specifies the JIT execution engine mode.
ob_query_timeout	The query timeout period.
ob_read_consistency	The read consistency level.
big_tables	Specifies whether to enable large table queries. If this variable is enabled, you can use the features of large MyISAM tables. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_prune_level	Controls the behavior of the query optimizer. The optimizer skips unnecessary query plans based on the estimated number of rows accessed from each table, thereby reducing query compilation time. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_search_depth	The maximum depth of query execution plans to be searched by the optimizer. The default value is `62`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_switch	Specifies the behavior options of the optimizer to enable or disable specific features. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_trace	Enables the query optimizer trace feature for debugging and analyzing query execution plans. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_trace_features	Specifies the features to be included in the optimizer trace. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_trace_limit	The maximum number of trace entries for the optimizer. The default value is `1`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
optimizer_trace_max_mem_size	The maximum memory usage for the optimizer trace. The default value is `16384`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
range_optimizer_max_mem_size	The maximum memory usage for the range optimizer. The default value is `8388608`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
show_create_table_verbosity	Specifies whether to display the row format when a table is created. The default value is `OFF`. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect and no error is returned.
sql_big_selects	Specifies whether to enable large queries. The default value is `ON`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, setting this variable does not take effect.

Variable	Description
ob_create_table_strict_mode	Specifies the strict mode for table creation.
ob_default_replica_num	Specifies the default number of replicas for tables in each cluster.
recyclebin	Specifies whether to enable the recycle bin.
master_info_repository	Specifies whether to record metadata in the mysql table of the InnoDB system database or as a file in the data directory. The default value is `FILE`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
gtid_next	Specifies the GTID value of the next transaction. The default value is `AUTOMATIC`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
ob_enable_truncate_flashback	Specifies whether to enable truncate flashback.

Variable	Description
ob_enable_plan_cache	Controls whether to enable the PL cache module.
ob_enable_plan_cache	Specifies whether to enable the Plan Cache.
ob_bnl_join_cache_size	Specifies the amount of data cached in each Batch Nested Loop Join (BNLJ) operation.

Variable	Description
group_concat_max_len	Specifies the maximum length of the result of the `GROUP_CONCAT()` function.
interactive_timeout	Specifies the number of seconds for which the server waits for activity before closing an interactive connection.
wait_timeout	Specifies the number of seconds for which the server waits for activity before closing a noninteractive connection.

Variable	Description
session_track_gtids	Specifies whether to return GTID information to the client. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.
session_track_transaction_info	Specifies whether to track the transaction status of the current session. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. However, the setting does not take effect.

Variable	Description
innodb_strict_mode	Specifies the SQL syntax check mode.
information_schema_stats_expiry	Specifies the number of seconds for the server to retrieve data from the storage engine and replace cached data. The default value is `86400`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
low_priority_updates	Specifies whether to control the priority of INSERT, UPDATE, DELETE, and REPLACE statements. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
max_error_count	Specifies the maximum number of errors, warnings, and notifications that can be stored in the diagnostic context. The default value is `64`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
max_insert_delayed_threads	Specifies the maximum number of threads for executing INSERT DELAYED statements. The default value is `20`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
eq_range_index_dive_limit	Specifies whether the optimizer performs index dives during equal-range queries. The default value is `200`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable	Description
default_storage_engine	Displays the default storage engine of an OBServer node.
ob_capability_flag	Specifies the capabilities of an OBServer node. This variable is used for capability negotiation with a proxy to inform the proxy of the supported and unsupported features of the OBServer node.
ob_compatibility_mode	Specifies the compatibility mode of a tenant.
ob_proxy_partition_hit	Specifies whether obproxy sends SQL requests for data to the OBServer nodes where the data resides.
ob_org_cluster_id	Specifies the `CLUSTER_ID` of an OceanBase cluster.
ob_route_policy	Specifies the routing policy for selecting data replicas in an OBServer node.
slave_allow_batching	Specifies whether to enable batch updates for replication threads. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable	Description
ob_enable_hash_group_by	Specifies whether to enable the Hash Group by path.

Variable	Description
ob_temp_tablespace_size_percentage	Specifies the percentage limit for the size of the temporary tablespace in the tenant's disk.
range_alloc_block_size	Specifies the size of the block allocated during range optimization. The default value is `4096` bytes. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable name	Description
ndb_allow_copying_alter_table	Specifies whether to allow `ALTER TABLE` and other DDL statements to use the copy operation on a table. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_autoincrement_prefetch_sz	Specifies the number of auto-increment values to be prefetched. This value can affect the performance and concurrency of auto-increment columns. The default value is `1`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_blob_read_batch_bytes	Specifies the size of BLOB data to be read in batches in an NDB cluster. The unit is bytes. The default value is `65536`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_blob_write_batch_bytes	Specifies the size of BLOB data to be written in batches in an NDB cluster. The unit is bytes. The default value is `65536`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_deferred_constraints	Specifies whether to delay constraint checks on a table. The default value is `0`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_force_send	Specifies whether to immediately send the cache to NDB without waiting for other threads. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_fully_replicated	Specifies whether to fully replicate a new table. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_index_stat_enable	Specifies whether to use NDB index statistics in query optimization. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_index_stat_option	Specifies the options for generating NDB index statistics. The default value is `loop_checkon=1000ms,loop_idle=1000ms,loop_busy=100ms,update_batch=1,read_batch=4,idle_batch=32,check_batch=32,check_delay=1m,delete_batch=8,clean_delay=0,error_batch=4,error_delay=1m,evict_batch=8,evict_delay=1m,cache_limit=32M,cache_lowpct=90`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_join_pushdown	Specifies whether to enable the join pushdown optimization feature in the storage engine. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_log_binlog_index	Specifies whether to insert the mapping between epochs and binlog positions into the ndb_binlog_index table. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_log_exclusive_reads	Specifies whether to use an exclusive lock to record primary key reads. The default value is `OFF`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_row_checksum	Specifies the checksum value of a table row. If the value is `1`, the checksum value of each row is calculated and saved. If the value is `0`, the checksum of table rows is not checked. The default value is `1`. Note This variable is available starting with MySQL 5.7. The related feature is not supported. You can query and set this variable. However, setting this variable does not take effect and does not return an error.
ndb_table_no_logging	Controls the logging behavior of NDB tables. When the value is `ON`, all tables created or modified using the NDB storage engine are in a non-logging state. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndb_table_temporary	Specifies the behavior of temporary tables when using the NDB storage engine. When the value is `ON`, NDB tables are not written to disk. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndb_use_exact_count	Specifies whether to force NDB to use record counts to accelerate `SELECT count(*)` queries. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndb_use_transactions	Controls whether to enable transaction support for NDB. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndbinfo_max_bytes	Only for testing and debugging. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndbinfo_max_rows	Only for testing and debugging. The default value is `10`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.
ndbinfo_show_hidden	Specifies whether to display the underlying internal tables of the `ndbinfo` database in the MySQL client. The default value is `OFF`. Note This variable is only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings will not take effect and will not generate errors.

Variable	Description
runtime_bloom_filter_max_size	The maximum memory size used by a runtime Bloom filter, in bytes.
runtime_filter_max_in_num	The number of distinct values in a column for a runtime IN filter.
runtime_filter_type	The type of a runtime filter at the tenant level.
runtime_filter_wait_time_ms	The maximum wait time for a runtime filter.

Variable	Description
lc_time_names	The language for displaying date and month names and abbreviations.
timestamp	`TIMESTAMP` is the timestamp, in seconds. This variable affects the result of `select now(6)`.
nls_calendar	The calendar system used by the database.
nls_language	The default language for database internationalization. It is used for prompts, dates, month names, and the default values of `NLS_SORT` and `NLS_DATE_LANGUAGE`.
error_on_overlap_time	Whether to return an error when there is ambiguity in the time zone overlap area.
nls_territory	The current region for database internationalization. It is used in combination with `nls_language`.
time_zone	The time zone for the current tenant session. It supports the offset format `'+08:00'` and the region format `Asia/Shanghai`.
show_old_temporals	Whether to display the old timestamp columns. The default value is `OFF`. Note This variable is only used for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.
date_format	The default date format. The default value is `%Y-%m-%d`. Note This variable is only used for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.
datetime_format	The default date and time format. The default value is `%Y-%m-%d %H:%i:%s`. Note This variable is only used for compatibility with MySQL 5.7. The related features are not supported. You can query this variable, but you cannot set it.

Variable	Description
updatable_views_with_limit	Whether to allow UPDATE or DELETE operations on a view with the LIMIT clause. The default value is `1`. Note This variable is only used for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable name	Description
autocommit	Specifies whether to automatically commit transactions.
ob_proxy_set_trx_executed	Specifies whether to send the `START TRANSACTION Syntax` statement to the OBServer node through the OBProxy node.
ob_trace_info	Used to pass through trace information, which can be persisted to the REDO log.
nls_date_language	Specifies the default language for date in database internationalization.
ob_trx_idle_timeout	Specifies the transaction idle timeout, which is the time interval between two statements in a transaction.
ob_trx_lock_timeout	Specifies the lock wait timeout for a transaction.
ob_trx_timeout	Specifies the transaction timeout.
transaction_isolation	Specifies the transaction isolation level.
transaction_read_only	Controls whether to allow only read-only transactions.
tx_isolation	Specifies the transaction isolation level.
tx_read_only	Specifies whether to set a transaction to read-only.
gtid_owned	Stores the GTID used and owned by the current session. The default value is `NULL`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query the variable, but cannot set it.
transaction_alloc_block_size	Specifies the initial memory block size allocated to each transaction. The default value is `8192`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set the variable, but the setting does not take effect.
transaction_allow_batching	Specifies whether to enable statement batching within the same transaction. The default value is `OFF`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set the variable, but the setting does not take effect.
transaction_prealloc_size	Specifies the size of the memory block preallocated for each transaction. The default value is `4069`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set the variable, but the setting does not take effect.
transaction_write_set_extraction	Specifies the algorithm type for generating identifiers for transaction-related writes. The default value is `OFF`. Note This variable is for MySQL 5.7 compatibility. The related features are not supported. You can query and set the variable, but the setting does not take effect.

Variable name	Description
explicit_defaults_for_timestamp	Specifies whether to enable non-standard behavior for the timestamp data type when handling default values and null values.
nls_currency	Specifies the local currency symbol for the `L` element of the number format.
nls_date_format	Controls the format for converting date types to strings and for implicitly converting strings to date types.
nls_dual_currency	Specifies the local currency symbol for the `U` element of the number format.
nls_iso_currency	Specifies the local currency symbol for the `C` element of the number format.
nls_length_semantics	Specifies the length semantics for the CHAR and VARCHAR2 data types.
nls_nchar_conv_excp	Controls whether to report an error when data is lost during conversion between NCHAR/NVARCHAR2 and CHAR/VARCHAR2.
nls_numeric_characters	Controls the characters used for decimal separators and thousand separators in number-to-string and string-to-number conversions.
nls_timestamp_format	Controls the format for converting TIMESTAMP or TIMESTAMP_LTZ types to strings and for implicitly converting strings to TIMESTAMP or TIMESTAMP_LTZ types.
nls_timestamp_tz_format	Controls the format for converting TIMESTAMP_TZ types to strings and for implicitly converting strings to TIMESTAMP_TZ types.
ob_default_lob_inrow_threshold	Specifies the default in-row storage threshold for LOB fields when creating a table.

Variable	Description
cursor_sharing	Specifies whether to parameterize SQL statements.
have_profiling	Specifies whether to enable query performance analysis. The default value is `NO`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query this variable but cannot set it.
max_sp_recursion_depth	Specifies the maximum number of recursive calls allowed for a stored procedure.
ob_enable_blk_nestedloop_join	Specifies whether to enable block nested loop join.
ob_pl_block_timeout	Specifies the maximum timeout period for PL.
profiling	Specifies whether to enable or disable statement analysis. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.
profiling_history_size	Specifies the number of query performance records to be saved. The default value is `15`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.
sql_mode	Specifies the SQL mode. Different SQL modes have significant impacts on operations such as insertions.
sql_quote_show_create	Specifies whether to enable reference identifiers for the `SHOW CREATE TABLE` and `SHOW CREATE DATABASE` statements.
sql_safe_updates	Specifies whether to enable MySQL's SQL safe mode. The default value is `OFF`.
sql_select_limit	Specifies the maximum number of rows that a Select query can return.
sql_throttle_current_priority	Specifies the throttling priority. Requests on sessions where `sql_throttle_current_priority` is less than `sql_throttle_priority` will be throttled.
ob_enable_parameter_anonymous_block	Specifies whether to enable anonymous block parameterization for the current session.
parser_max_mem_size	Specifies the maximum memory size available to the parser. The default value is `18446744073709551615`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.

Variable	Description
innodb_lock_wait_timeout	Specifies the maximum time (in seconds) that an InnoDB transaction waits for a lock. The default value is `50`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.
innodb_table_locks	Specifies the behavior of InnoDB table-level locking. The default value is `ON`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.

Variable	Description
rand_seed1	Specifies the seed value for the random number generator. The default value is `0`. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.
rand_seed2	Specifies the additional seed value for the random number generator. The default value is ``. Note This variable is only for compatibility with MySQL 5.7. The related feature is not supported. You can query and set this variable, but the setting does not take effect.

Variable name	Description
binlog_row_image	Specifies whether to record full-column logs.
ob_enable_show_trace	Specifies whether to use Show Trace logs.
tracefile_identifier	Adds specified content to logs to facilitate filtering of row iteration trace logs.
ob_log_level	Specifies the log level for the session. If not specified, the system log level is used.

Name	Description
pseudo_slave_mode	Specifies whether to enable the pseudo-slave mode on the server. The default value is `OFF`. Note This variable is compatible with MySQL 5.7. The related functionality is unavailable. You can query and set this variable. The setting will not be applied but no error will be returned.
pseudo_thread_id	Specifies the ID of the session thread. The default value is `2147483647`. Note This variable is provided for compatibility with MySQL 5.7. The related features are not supported, but you can query and set this variable. The behavior of setting this variable does not result in an error but does not take effect.
rbr_exec_mode	Set the mode to IDEMPOTENT or STRICT for the session thread. Default value is
`STRICT`. Note This variable is for compatibility with MySQL 5.7. You can query or set it without encountering an error. However, its value does not take effect.
insert_id	This variable specifies the insert ID that is used by subsequent `INSERT` or `ALTER TABLE` statements to automatically generate and insert an auto-incrementing value. The default value is `0`. Note This variable is only provided for compatibility with MySQL 5.7. The related functionality is not supported, so querying and setting this variable is allowed. Although the setting behavior does not trigger an error, it does not take effect.
join_buffer_size	The minimum buffer size for join operations of pure index scan, range index scan, or full table scan. The unit is bytes. The default value is `262144`. Note This variable is for MySQL compatibility. You can query and set the variable without causing an error. However, the settings do not take effect.
max_join_size	This variable specifies the maximum number of rows allowed in Join operations. The default value is `18446744073709547520`. Note This variable is retained for MySQL 5.7 compatibility. It is not supported and will not take effect. You can execute the `SET` statement to modify it without any error.
max_length_for_sort_data	Specifies the truncation value of index value size for determining which file sorting algorithm to use. The default value is `1024`. Note This variable is only for MySQL 5.7 compatibility. The related feature is not supported, but the value can be queried and set. Setting the value will not produce an error, but the change will not take effect.
max_sort_length	The number of bytes used for sorting numeric values. The default value is `1024`. Note This variable is for compatibility with MySQL 5.7. You can query and set the variable. However, changes do not take effect.
min_examined_row_limit	Specifies the minimum number of rows to be examined in a query before the query is recorded to the slow query log. Queries that examine fewer than the specified minimum number of rows are not recorded. The default value is `0`. Note This variable is for MySQL 5.7 compatibility. It is not supported in TiDB. You can execute the `SET` statement to modify the variable, but the variable has no effect in the current session.
multi_range_count	Specifies the maximum number of Range types allowed in a query statement. The default value is `256`. Note This variable is introduced only for compatibility with MySQL 5.7. The related feature is unavailable, and this variable can be queried and set. Setting this variable does not result in an error, but the setting does not take effect.
query_alloc_block_size	The size, in bytes, of memory blocks allocated to objects during statement parsing and execution. The default value is `8192`. Note This variable is compatible with MySQL 5.7. The corresponding feature is not supported. You can query and set the value, but modifications are not effective.
query_prealloc_size	The size of the fixed buffer used for statement parsing and execution. Unit: bytes. Default value: `8192`. Note This variable is provided only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable. The setting does not take effect and no error is returned.
sort_buffer_size	Specifies the size of the sort buffer in bytes. The default value is `262144`. Note This variable is for compatibility with MySQL 5.7. It cannot be modified. However, the system does not report an error when you set it.
sql_buffer_result	Specifies whether to store the result of the `SELECT` statement in a temporary table. The default value is `0`. Note This variable is only supported for MySQL 5.7 compatibility. The specified value is accepted but has no effect. You can query the variable and set it to any value, but the setting takes no effect.
myisam_repair_threads	The number of concurrent threads to be used for repairing the MyISAM table. The default value is `1`. Note This variable is provided only for MySQL 5.7 compatibility. The related features are not supported. You can query and modify this variable, but the modifications do not take effect.
myisam_sort_buffer_size	The size of the buffer used for sorting MyISAM indexes during REPAIR TABLE operations or when creating indexes with CREATE INDEX or ALTER TABLE. The unit is bytes. The default value is `8388608`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
myisam_stats_method	The method used by the server to calculate NULL values when collecting statistics on the distribution of index values in MyISAM tables. The default value is `nulls_unequal`, which treats NULL values as regular values and treats them the same as other values. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
preload_buffer_size	The size of the buffer used for preloading indexes. The unit is bytes. The default value is `32768`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
read_buffer_size	The size of the buffer used for reading data. The unit is bytes. The default value is `131072`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
read_rnd_buffer_size	The size of the buffer used for reading data from MyISAM tables. It is also used for multi-range read optimization for any storage engine. The unit is bytes. The default value is `262144`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
keep_files_on_create	When the `DATA DIRECTORY` or `INDEX DIRECTORY` option is not used to specify the location of data files or index files, this variable controls whether the server retains existing files in the corresponding directory when creating a MyISAM table. The default value is `OFF`, which means that existing files are overwritten. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
max_heap_table_size	The maximum size to which a memory table created by a user can grow. The unit is bytes. The default value is `16777216`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
bulk_insert_buffer_size	The size of the buffer used for bulk insert operations. The unit is bytes per thread. The default value is `8388608`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
max_delayed_threads	The maximum number of threads that can be created to handle INSERT DELAYED statements. The default value is `20`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
sql_log_off	Specifies whether to enable (OFF) or disable (ON) the logging of regular queries for the current session. The default value is `OFF`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
thread_pool_high_priority_connection	Specifies whether to reserve idle threads for high-priority connections in the thread pool. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.
version_tokens_session_number	An internal variable. The default value is `0`. Note This variable is available only for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the settings do not take effect and no errors are reported.

Variable name	Description
foreign_key_checks	Specifies whether to check foreign key constraints in DML/DDL statements.

Variable name	Description
ob_enable_transformation	Specifies whether to enable the rewrite feature of the SQL optimizer.
optimizer_capture_sql_plan_baselines	Specifies whether to automatically capture new plans to the Plan Baseline.
optimizer_features_enable	Specifies whether to enable the optimizer features of different OceanBase Database versions.
optimizer_use_sql_plan_baselines	Specifies whether to use the Plan Baseline plan.

Variable name	Description
auto_increment_increment	Specifies the auto-increment step size. This variable is used only for MySQL clients.
auto_increment_offset	Specifies the starting value of the `AUTO_INCREMENT` column.
identity	`identity` and the `last_insert_id` variable are synonyms. You can execute the `select @@identity` statement to query the value.
last_insert_id	Returns the value of the auto-increment column of the last inserted row in the current session.
div_precision_increment	Specifies the increment of the precision of the result of a division operation based on the precision of the dividend. This is a MySQL-compatible feature.
sql_auto_is_null	Specifies whether to obtain the value of the auto-increment column of the last inserted row.

Variable name	Description
character_set_client	The character set for statements sent by the client.
character_set_database	The character set for the default database.
character_set_filesystem	The character set for the filesystem.
character_set_results	The character set to which the server converts result sets and error messages before sending them back to the client.
character_set_server	The character set for the server.
character_set_system	The character set used by the server.
collation_connection	The character set and collation for the connection.
collation_database	The default character set and collation for the database.
collation_server	The default character set and collation for the server.
nls_comp	The collation rules for string values.
nls_sort	The sorting rules for string values.
sql_warnings	Controls whether an information string is generated for a single-row INSERT statement when an alert occurs.
default_collation_for_utf8mb4	The default collation for the utf8mb4 character set, which is `utf8mb4_general_ci` by default. Note This variable is for compatibility with MySQL 5.7. The related features are not supported. You can query and set this variable, but the setting will not take effect.

Variable name	Description
group_replication_force_members	Specifies the list of member addresses in the format `host1:port1,host2:port2`. This variable is used to forcibly create a new group. After it is set, excluded members (those not specified in this variable) will not receive new view messages and will be blocked (write operations will be blocked). The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_group_name	Specifies the name of the group to which the current server belongs. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_gtid_assignment_block_size	Specifies the number of consecutive GTIDs to retain for each member. The default value is `1000000`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_ip_whitelist	Specifies the list of hosts (IP addresses or hostnames) that are allowed to connect to the group. These hosts are referred to as whitelist hosts. The default value is `AUTOMATIC`. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_local_address	The network address that group replication members use to provide access to other members in the group. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_ca	Specifies the path to the file containing the list of trusted SSL certificate authorities for distributed recovery connections. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_capath	Specifies the directory path to the certificates issued by the trusted SSL certificate authorities for distributed recovery connections. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_cert	Specifies the name of the SSL certificate file required to establish a secure connection for distributed recovery. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_cipher	Specifies the list of encryption algorithms allowed for SSL encryption. The available encryption algorithms depend on the version of the SSL library used to compile MySQL Server. Different SSL libraries support different encryption algorithms. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_crl	Specifies the file name containing the certificate revocation list. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_crlpath	Specifies the directory path containing the certificate revocation list files. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.
group_replication_recovery_ssl_key	Specifies the name of the SSL key file required to establish a secure connection for distributed recovery. The default value is empty. Note This variable is only for compatibility with MySQL 5.7. The related functionality is not supported. You can query and set it, but the settings will not take effect and no errors will be reported.

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Version information related attributes

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Read/write and query-related variables

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Scheduler-related

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