- **Description**: Uses bitmap indexes to scan the heap more efficiently. - **Performance**: Efficient for large datasets with selective conditions. - **Factors**: Pages fetched, rows scanned, disk I/O cost. - **Cost**: `io_cost * pages fetched + cpu_tuple_cost * rows scanned` - ![[ex_bmp_heap.svg|200x200]] - **Operates on**: [[Math and Computation/Databases/Postgres/Structures/Index|Index]] [[Page]]