Managing the cube summary table refresh

In environments where a monitoring context has many instances, computing aggregates for measures in dimensional analysis might take a long time and adversely affect dashboard performance. Precomputing aggregates and storing them in database summary tables called materialized query tables (MQTs) can significantly improve query performance.

An MQT, also known as a cube summary table, persists (materializes) the precomputed result of a query involving one or more database tables. After the MQT is created and populated, the query optimizer of the database makes a cost-based decision to route the query to the MQT to satisfy queries, instead of routing the query to the original underlying tables. Adding cube summary tables can improve the performance of queries used to generate multidimensional reports in gigabyte-sized DB2 databases.

You enable the cube summary refresh table service by generating cube summary tables. You can then view and schedule the cube summary table refresh services using the administrative console.

Important: Before you can add the cube summary tables, you must enable the data movement service.

MQTs are supported only when you are using DB2® as the IBM® Business Monitor database.

Note: If you are using Oracle, you can use materialized views to persist the precomputed result of a query, as described in "MONITOR database considerations for Oracle."