Description
You can execute the ALTER DATABASE statement to modify the attributes of a database.
Syntax
alter_database_stmt:
ALTER DATABASE [database_name] [SET] alter_specification_list;
alter_specification_list:
alter_specification [alter_specification ...]
alter_specification:
[DEFAULT] {CHARACTER SET | CHARSET} [=] charset_name
| [DEFAULT] COLLATE [=] collation_name
| REPLICA_NUM [=] int_num
| PRIMARY_ZONE [=] zone_name
| {READ ONLY | READ WRITE}
| DEFAULT TABLEGROUP [=] {NULL | table_group_name}
Parameters
| Parameter | Description |
|---|---|
| database_name | The name of the database for which you want to modify attributes. The current default database is modified if you leave this parameter empty. |
| CHARSET charset_name | The character set that you want to modify. |
| COLLATE collation_name | The collation. |
| REPLICA_NUM int_num | The number of replicas. |
| PRIMARY_ZONE zone_name | The primary zone. |
| READ ONLY | READ WRITE | The attribute of the database. Valid values: READ ONLY and READ WRITE. |
| DEFAULT TABLEGROUP table_group_name | The default table group of the database. A NULL value indicates that no default table group is specified for the database. |
Examples
- Execute the following statements to modify database test2. Set the character set to UTF8MB4 and the collation to UTF8MB4_BIN. Set the database attribute to READ WRITE.
OceanBase(admin@test)>alter database test2 DEFAULT CHARACTER SET UTF8MB4;
Query OK, 0 rows affected (0.03 sec)
OceanBase(admin@test)>alter database test2 DEFAULT COLLATE UTF8MB4_BIN;
Query OK, 0 rows affected (0.03 sec)
OceanBase(admin@test)>alter database test2 READ WRITE;
Query OK, 0 rows affected (0.02 sec)