transaction_isolation

Description

transaction_isolation specifies the transaction isolation level. It has the same functionality as the system variable tx_isolation. You can set either of them.

Privilege requirements

• Query variables

  • Global level

    The sys tenant and all user tenants can execute the SHOW VARIABLES statement or query the SYS.TENANT_VIRTUAL_GLOBAL_VARIABLE view (Oracle-compatible mode) or the information_schema.GLOBAL_VARIABLES view (MySQL-compatible mode) to obtain the values of global system variables.

  • Session level

    The sys tenant and all user tenants can execute the SHOW VARIABLES statement or query the SYS.TENANT_VIRTUAL_SESSION_VARIABLE view (Oracle-compatible mode) or the information_schema.SESSION_VARIABLES view (MySQL-compatible mode) to obtain the values of session system variables.

• Modify variables

  • Global level

    • The sys tenant can directly modify the values of global system variables.

    • MySQL user tenants must have the SUPER or ALTER SYSTEM privilege to modify the values of global system variables.

    • Oracle user tenants must have the ALTER SYSTEM privilege to modify the values of global system variables.

  • Session level

    The sys tenant and all user tenants can directly modify the values of session system variables in their own tenants.

Attributes

Examples

Set the transaction isolation level to READ-COMMITTED.

• Session level

  obclient> SET transaction_isolation = 'READ-COMMITTED';
  

• Global level

  obclient> SET GLOBAL transaction_isolation = 'READ-COMMITTED';
  

References

For more information about transaction isolation levels, see Overview.