This topic describes incompatibilities between MySQL databases and MySQL-compatible tenants of OceanBase Database when you change the type of an unconstrained column.
The following table describes the types to which you can change a column by executing the ALTER TABLE table_name MODIFY/CHANGE COLUMN DDL statement in a MySQL database and a MySQL-compatible tenant of OceanBase Database.
Note
In the following table, a hyphen (-) means N/A. 'All' means all types.
Column type in a MySQL database |
Supported target type other than the original type |
Column type in a MySQL-compatible tenant of OceanBase Database |
Supported target type other than the original type |
|---|---|---|---|
| INT | All | INTEGER | BIGINT |
| TINYINT | All | TINYINT | INTEGER SMALLINT MEDIUMINT BIGINT BOOLEAN |
| SMALLINT | All | SMALLINT | INTEGER BIGINT MEDIUMINT |
| MEDIUMINT | All | MEDIUMINT | INTEGERBIGINT |
| BIGINT | All | BIGINT | - |
| BOOL | All | BOOLEAN | INTEGER TINYINT SMALLINT MEDIUMINT BIGINT |
| DECIMAL | All | DECIMAL | NUMERIC |
| NUMERIC | All | NUMERIC | DECIMAL |
| REAL | All | FLOAT | - |
| DOUBLE | All | DOUBLE | - |
| FLOAT | All | FLOAT | - |
| BIT | All | BIT | - |
| CHAR | All | CHAR | - |
| NCHAR | All | CHAR | - |
| VARCHAR | All | VARCHAR | TINYTEXT TEXT LONGTEXT MEDIUMTEXT |
| BINARY | All | BINARY | - |
| VARBINARY | All | VARBINARY | BLOB TINYBLOB MEDIUMBLOB LONGBLOB |
| LONG_VARBINARY | All | BLOB | - |
| YEAR | All | YEAR | - |
| DATE | All | DATE | - |
| TIME | All | TIME | - |
| TIMESTAMP | All | TIMESTAMP | - |
| DATETIME | All | DATETIME | - |
| TINYBLOB | All | TINYBLOB | BLOB LONGBLOB MEDIUMBLOB |
| MEDIUMBLOB | All | MEDIUMBLOB | - |
| BLOB | All | BLOB | - |
| LONGBLOB | All | LONGBLOB | - |
| TINYTEXT | All | TINYTEXT | TEXT LONGTEXT MEDIUMTEXT |
| MEDIUMTEXT | All | MEDIUMTEXT | - |
| TEXT | All | TEXT | - |
| LONGTEXT | All | LONGTEXT | - |
| ENUM | All | ENUM | - |
| SET | All | SET | - |
| JSON | All | JSON | - |