Overview and Requirements - OLAP

The OLAP API requires a specific set of materialized views for each OLAP Catalog cube that maps to a star schema. The cube must be mapped to a single fact table, and the fact table may contain only lowest-level data. For each cube, there must be a separate dimension materialized view for each hierarchy of each of the cube's dimensions. For the cube's fact table, there is a single materialized view, created with GROUP BY GROUPING SETS syntax.

Use the Oracle Data Management package, DBMS_ODM, to create materialized views.

Materialized Views Required for a Cube

The OLAP API requires a dimension materialized view for each hierarchy associated with a cube. For example, the SALES_CUBE cube in the Sales History (SH) schema requires seven dimension materialized views, as illustrated in Table. For the cube's fact table, the OLAP API requires a single grouping set materialized view.

Number of Dimension Materialized Views for SH.SALES_CUBE

Materialized Views and OLAP Metadata

Before creating materialized views, you must create OLAP metadata for the star schema. You can use Oracle Enterprise Manager, or you can write a script using the CWM2 packages.