transaction_read_only

Description

transaction_read_only specifies whether to allow only read-only transactions.

Privilege requirements

• Query variables

  • Global level

    sys tenants and all user tenants can execute the SHOW VARIABLES statement or query the SYS.TENANT_VIRTUAL_GLOBAL_VARIABLE view (Oracle mode) or the information_schema.GLOBAL_VARIABLES view (MySQL mode) to obtain the value of a global system variable.

  • Session level

    sys tenants and all user tenants can execute the SHOW VARIABLES statement or query the SYS.TENANT_VIRTUAL_SESSION_VARIABLE view (Oracle mode) or the information_schema.SESSION_VARIABLES view (MySQL mode) to obtain the value of a session system variable.

• Modify variables

  • Global level

    • sys tenants can modify the value of a global system variable.

    • MySQL user tenants must have the SUPER or ALTER SYSTEM privilege to modify the value of a global system variable.

    • Oracle user tenants must have the ALTER SYSTEM privilege to modify the value of a global system variable.

  • Session level

    sys tenants and all user tenants can modify the value of a session system variable.

Attributes

Usage

If transaction_read_only is set to True, you cannot execute DML statements.

Examples

Allow non-read-only transactions.

• Session level

  obclient> SET transaction_read_only = False;
  

• Global level

  obclient> SET GLOBAL transaction_read_only = False;