From c0f80d78a1d2a940a825beeb394f8cd025d260c0 Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Mon, 26 Feb 2024 18:35:28 -0500 Subject: [PATCH v5 06/14] EXPLAIN Bitmap table scan also count no visible tuple pages 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 constructured bitmap, so it doesn't make sense to omit pages without visible tuples. --- src/backend/executor/nodeBitmapHeapscan.c | 15 ++++++++++----- src/test/regress/expected/partition_prune.out | 4 +++- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/src/backend/executor/nodeBitmapHeapscan.c b/src/backend/executor/nodeBitmapHeapscan.c index 3439c02e989..75e896074bf 100644 --- a/src/backend/executor/nodeBitmapHeapscan.c +++ b/src/backend/executor/nodeBitmapHeapscan.c @@ -225,6 +225,8 @@ BitmapHeapNext(BitmapHeapScanState *node) for (;;) { + bool valid; + CHECK_FOR_INTERRUPTS(); /* @@ -244,17 +246,20 @@ BitmapHeapNext(BitmapHeapScanState *node) BitmapAdjustPrefetchIterator(node, tbmres->blockno); - if (!table_scan_bitmap_next_block(scan, tbmres)) - { - /* AM doesn't think this block is valid, skip */ - continue; - } + valid = table_scan_bitmap_next_block(scan, tbmres); if (tbmres->ntuples >= 0) node->exact_pages++; else node->lossy_pages++; + if (!valid) + { + /* AM doesn't think this block is valid, skip */ + continue; + } + + /* Adjust the prefetch target */ BitmapAdjustPrefetchTarget(node); } diff --git a/src/test/regress/expected/partition_prune.out b/src/test/regress/expected/partition_prune.out index b41950d923b..7b1b1e97033 100644 --- a/src/test/regress/expected/partition_prune.out +++ b/src/test/regress/expected/partition_prune.out @@ -2812,6 +2812,7 @@ update ab_a1 set b = 3 from ab where ab.a = 1 and ab.a = ab_a1.a; Index Cond: (a = 1) -> Bitmap Heap Scan on ab_a1_b3 ab_a1_3 (actual rows=0 loops=1) Recheck Cond: (a = 1) + Heap Blocks: exact=1 -> Bitmap Index Scan on ab_a1_b3_a_idx (actual rows=1 loops=1) Index Cond: (a = 1) -> Materialize (actual rows=1 loops=1) @@ -2827,9 +2828,10 @@ update ab_a1 set b = 3 from ab where ab.a = 1 and ab.a = ab_a1.a; Index Cond: (a = 1) -> Bitmap Heap Scan on ab_a1_b3 ab_3 (actual rows=0 loops=1) Recheck Cond: (a = 1) + Heap Blocks: exact=1 -> Bitmap Index Scan on ab_a1_b3_a_idx (actual rows=1 loops=1) Index Cond: (a = 1) -(34 rows) +(36 rows) table ab; a | b -- 2.37.2