enable_mv_binlog_minimal_mode

Description

enable_mv_binlog_minimal_mode specifies whether to enable the binlog minimal mode for materialized view incremental refresh.

Privilege requirements

• Query the parameter

  You can execute the SHOW PARAMETERS statement or query the GV$OB_PARAMETERS view to obtain the value of this parameter in the sys tenant and all user tenants.

• Modify the parameter

  You can modify this parameter in the sys tenant and user tenants.

Attributes

Considerations

• The enable_mv_binlog_minimal_mode parameter affects only DML operations on materialized views. It does not affect other DML operations.

• The enable_mv_binlog_minimal_mode parameter is independent of binlog_row_image. It specifies the special path for materialized view scenarios.

  • If you enable the enable_mv_binlog_minimal_mode parameter, DML operations on materialized views use the binlog minimal mode, even if the binlog_row_image parameter is set to full.

• Enabling the enable_mv_binlog_minimal_mode parameter improves the refresh performance of materialized views. However, this parameter simplifies the CLOG content. If downstream links (such as CDC + OMS) rely on the complete CLOG of materialized views for migration and synchronization, enabling this parameter may cause synchronization errors. Therefore, we recommend that you do not enable this parameter if you have downstream data synchronization requirements involving materialized views.

Examples

1. Enable the binlog minimal mode for materialized view incremental refresh.

   obclient> ALTER SYSTEM SET enable_mv_binlog_minimal_mode = True;
   

2. Create a table named test_tbl1.

   obclient> CREATE TABLE test_tbl1(col1 INT, col2 INT, col3 INT);
   

3. Create a materialized view named mv1_t1.

   obclient> CREATE MATERIALIZED VIEW mv1_t1
       REFRESH FAST
       AS SELECT col2, COUNT(*) cnt
          FROM test_tbl1
          GROUP BY col2;
   

4. When you perform incremental refresh, DML operations use the binlog minimal mode.

   obclient> CALL DBMS_MVIEW.REFRESH('mv1_t1', 'f');
   

5. Disable the binlog minimal mode for materialized view incremental refresh.

   obclient> ALTER SYSTEM SET enable_mv_binlog_minimal_mode = False;