Note
This view was introduced in OceanBase Database V4.2.0.
Purpose
The oceanbase.DBA_OB_DATA_DICTIONARY_IN_LOG view displays the location range of data dictionaries in the system log stream so that Change Data Capture (CDC) can conveniently consume the data dictionaries.
Columns
Column |
Type |
Nullable? |
Description |
|---|---|---|---|
| SNAPSHOT_SCN | bigint(20) unsigned | NO | The snapshot system change number (SCN) of the tenant when the data dictionary was generated. |
| REPORT_TIME | timestamp(6) | YES | The time when the data dictionary was reported to the internal table, in µs. |
| START_LSN | bigint(20) unsigned | NO | The log sequence number (LSN) of the first log when the data dictionary was persisted in the log stream with the ID 1 of the tenant. |
| END_LSN | bigint(20) unsigned | NO | The LSN of the last log when the data dictionary was persisted in the log stream with the ID 1 of the tenant. |
Sample query
Query the location range of data dictionaries of all user tenants in the system log stream from the sys tenant.
obclient [oceanbase]> SELECT * FROM oceanbase.CDB_OB_DATA_DICTIONARY_IN_LOG;
The query result is as follows:
+-----------+---------------------+----------------------------+-----------+-----------+
| TENANT_ID | SNAPSHOT_SCN | REPORT_TIME | START_LSN | END_LSN |
+-----------+---------------------+----------------------------+-----------+-----------+
| 1002 | 1723084121964378000 | 2024-08-08 10:28:42.014127 | 10713062 | 10713062 |
| 1002 | 1723170522400303000 | 2024-08-09 10:28:42.439283 | 139661239 | 139661239 |
| 1004 | 1723084155932969000 | 2024-08-08 10:29:15.983581 | 16136726 | 16136726 |
| 1004 | 1723170556335749000 | 2024-08-09 10:29:16.366229 | 148555952 | 148555952 |
+-----------+---------------------+----------------------------+-----------+-----------+
4 rows in set