- **Description**: Combines multiple bitmap index scans using a logical expressions - **Performance**: Combines bitmap index scans efficiently. - **Factors**: Number of bitmaps, bitmap scan selectivity. - **Cost**: Sum of bitmap scan costs + `cpu_operator_cost * number of bitmaps` - ![[ex_bmp_and.svg|200x200]] ![[ex_bmp_or.svg|200x200]] - **Operates on**: [[Math and Computation/Databases/Postgres/Structures/Index|Index]]