A127 Query Optimization for Selections Using Bitmaps
نویسنده
چکیده
Bitmaps are popular indexes for Data Warehouse (DW) applications and most database management systems (DBMSs) ooer them today. This paper analyzes query optimization issues for selection operations using bitmaps. Both continuous and discrete selection criteria are considered. Query optimization is categorized into static and dynamic optimization. The static optimization issues discussed are the optimal design of bitmaps, and algorithms based on tree and logical reduction. The dynamic optimization issue includes the approach of inclusion/exclusion for both bit-sliced indexes and encoded bitmap indexes.
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