Method for executing star queries

摘要

A method and apparatus for processing star queries is provided. According to the method, a star query is transformed by adding to the star query subqueries that are not in the query. The subqueries are generated based on join predicates and constraints on dimension tables that are contained in the original query. The subqueries are executed, and the values returned by the subqueries are used to access one or more bitmap indexes built on columns of the fact table. The bitmaps retrieved for the values returned by each subquery are merged to create one subquery bitmap per subquery. An AND operation is performed on the subquery bitmaps, and the resulting bitmap is used to determine which data to retrieve from the fact table.