Secondary bitmap indexes with vertical and horizontal partitioning

Traditional bitmap indexes are utilized as a special type of primary or clustered indexes where the queries are answered by performing fast logical operations supported by hardware. Answers are mapped to the physical data by using the row id of each tuple. Bitmaps represent the i-th tuple in the original table with the i-th bit position of the index. Run-length compression is used to reduce the size of the bitmaps and it has been shown that ordered data is significantly better compressed. However, for large-scale and dynamic datasets it is infeasible to keep the data always sorted. Partitioning can be used to keep the data in smaller and manageable chunks, where a different bitmap index is built for each chunk. We propose a novel bitmap index design with partitioning which serves as basis for non-clustered bitmap indexes. Individual bitmaps are not stored, only an Existence Bitmap (EB) for the existing ranks of the full table is maintained. This approach improves update performance o...

• Type: Conference
• Year: 2009
• Where: EDBT
• Authors: Guadalupe Canahuate, Tan Apaydin, Ahmet Sacan, Hakan Ferhatosmanoglu
• Keywords: Bitmap Indexes, Bitmaps, EDBT 2009, Traditional Bitmap Indexes