Foreign Key Index Type
Set the default index types built for foreign key columns of Dimension tables, Kpi Fact tables, Fact tables and Aggregate tables.
The options for SQL Server and DB2 are:
(None) - we will not define
BTREE - this is a standard index per key column
COVERING - this is a single index with all the key columns in it
The options for Oracle are:
(None) - will not be defined
BITMAP - This is the standard oracle bitmap index
BTREE - this is a standard index per key column
These defaults are applied when a table or index definition is created. They can be changed by selecting the Storage tab on the Properties screen of a table or an index.