|Oracle9i OLAP User's Guide
Release 2 (220.127.116.11)
Part Number A95295-02
When creating MVs for the OLAP API, you should create materialized views for each OLAP Catalog cube that represents a star schema. The cube must be mapped to a single fact table, and the fact table may contain only lowest-level data. For more information, see "Materialized Views and OLAP Metadata".
The number of fact materialized views for a cube depends on whether you using concatenated rollup style MVs or grouping set MVs.
If you use OLAP Summary Advisor, you will generate a separate concatenated rollup style MV for each combination of hierarchies in the cube. If you use
DBMS_ODM, you will generate a single grouping set style MV for the cube.
For example, the
SALES_CUBE cube in the Sales History (
SH) schema, described in Table 10-1, would have either one materialized view generated with grouping sets or four materialized views generated with concatenated rollup.
SALES_CUBE, there would be a separate concatenated rollup materialized view for the each of the following dimension hierarchy combinations.