You can use the Optimization Advisor to recommend
summary tables that can dramatically improve the performance of OLAP-style
queries.
This section includes the following topics:
Summary tables DB2® Warehouse uses DB2 summary tables to improve the
performance of queries issued to cube models and cubes. A summary
table is a special type of a materialized query table (MQT) that specifically
includes summary data.
Summary tables with functional dependencies and constraints The Optimization Advisor wizard utilizes information
about the relationships between data, such as functional dependencies
and constraints, to recommend summary tables that contain aggregated
measures and the level attributes that are necessary for the DB2 optimizer to efficiently answer
queries.
Overview of the optimization process Optimizing your star schema or snowflake schema
with DB2 Warehouse can
improve the performance of OLAP-style SQL queries. The optimization
process includes creating, implementing, and maintaining the summary
tables recommended by the Optimization Advisor.
Optimizing a cube model You can optimize a cube model to improve the
performance of OLAP style SQL queries.