Fix EXPLAIN Bitmap heap scan to count pages with no visible tuples
Heikki Linnakangas <heikki.linnakangas@iki.fi>
Fix EXPLAIN Bitmap heap scan to count pages with no visible tuples Previously, bitmap heap scans only counted lossy and exact pages for explain when there was at least one visible tuple on the page. heapam_scan_bitmap_next_block() returned true only if there was a "valid" page with tuples to be processed. However, the lossy and exact page counters in EXPLAIN should count the number of pages represented in a lossy or non-lossy way in the constructed bitmap, regardless of whether or not the pages ultimately contained visible tuples. Backpatch to all supported versions. Author: Melanie Plageman Discussion: https://www.postgresql.org/message-id/CAAKRu_ZwCwWFeL_H3ia26bP2e7HiKLWt0ZmGXPVwPO6uXq0vaA@mail.gmail.com Discussion: https://www.postgresql.org/message-id/CAAKRu_bxrXeZ2rCnY8LyeC2Ls88KpjWrQ%2BopUrXDRXdcfwFZGA@mail.gmail.com
Files
| Path | Change | +/− |
|---|---|---|
| src/backend/executor/nodeBitmapHeapscan.c | modified | +5 −5 |
| src/test/regress/expected/partition_prune.out | modified | +4 −1 |
Discussion
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