schema_history_archive_expire_time

Overview

The schema_history_archive_expire_time parameter specifies the retention period for multi-version historical archive data of schemas.

To prevent archived tables from growing indefinitely, OceanBase Database introduces Controlled GC (Garbage Collection). During collection, the archive GC cut-off version is calculated based on the schema_version corresponding to the recycle point and the retention period. Archived historical data is then deleted in batches.

Privilege requirements

• Query parameters

  Both the sys tenant and all user tenants can query this parameter using the SHOW PARAMETERS statement or the GV$OB_PARAMETERS view.

• Modify parameters

  Both the sys tenant and user tenants can modify this parameter.

Attributes

Configuration example

• System tenant

  • Stop the garbage collection for schema multi-version historical archive data in tenant tenant1.

    obclient(root@sys)[(none)]> ALTER SYSTEM SET schema_history_archive_expire_time = '0' TENANT = tenant1;
    

  • Set the retention period for multi-version historical archive data in the schema of tenant tenant1 to 90 days.

    obclient(root@sys)[(none)]> ALTER SYSTEM SET schema_history_archive_expire_time = '90d' TENANT = tenant1;
    

• User tenant

  • Stop GC for multi-version historical archive data of the current tenant's schema.

    obclient> ALTER SYSTEM SET schema_history_archive_expire_time = '0';
    

  • Set the retention period for multi-version historical archive data of schemas in this tenant to 90 days.

    obclient> ALTER SYSTEM SET schema_history_archive_expire_time = '90d';