Make bitmap heap scans show exact/lossy block info in EXPLAIN ANALYZE.

Etsuro Fujita

diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 7097eff9b114522b74b49816592b0933efaa28da..e604be31f9d741dc39835bd7c1526419d8034220 100644 (file)
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -85,6 +85,8 @@ static void show_sort_group_keys(PlanState *planstate, const char *qlabel,
                                         List *ancestors, ExplainState *es);
 static void show_sort_info(SortState *sortstate, ExplainState *es);
 static void show_hash_info(HashState *hashstate, ExplainState *es);
+static void show_tidbitmap_info(BitmapHeapScanState *planstate,
+                                                               ExplainState *es);
 static void show_instrumentation_count(const char *qlabel, int which,
                                                   PlanState *planstate, ExplainState *es);
 static void show_foreignscan_info(ForeignScanState *fsstate, ExplainState *es);
@@ -1250,7 +1252,13 @@ ExplainNode(PlanState *planstate, List *ancestors,
                        if (((BitmapHeapScan *) plan)->bitmapqualorig)
                                show_instrumentation_count("Rows Removed by Index Recheck", 2,
                                                                                   planstate, es);
-                       /* FALL THRU */
+                       show_scan_qual(plan->qual, "Filter", planstate, ancestors, es);
+                       if (plan->qual)
+                               show_instrumentation_count("Rows Removed by Filter", 1,
+                                                                                  planstate, es);
+                       if (es->analyze)
+                               show_tidbitmap_info((BitmapHeapScanState *) planstate, es);
+                       break;
                case T_SeqScan:
                case T_ValuesScan:
                case T_CteScan:
@@ -1878,6 +1886,29 @@ show_hash_info(HashState *hashstate, ExplainState *es)
        }
 }
 
+/*
+ * If it's EXPLAIN ANALYZE, show exact/lossy pages for a BitmapHeapScan node
+ */
+static void
+show_tidbitmap_info(BitmapHeapScanState *planstate, ExplainState *es)
+{
+       if (es->format != EXPLAIN_FORMAT_TEXT)
+       {
+               ExplainPropertyLong("Exact Heap Blocks", planstate->exact_pages, es);
+               ExplainPropertyLong("Lossy Heap Blocks", planstate->lossy_pages, es);
+       }
+       else
+       {
+               appendStringInfoSpaces(es->str, es->indent * 2);
+               appendStringInfoString(es->str, "Heap Blocks:");
+               if (planstate->exact_pages > 0)
+                       appendStringInfo(es->str, " exact=%ld", planstate->exact_pages);
+               if (planstate->lossy_pages > 0)
+                       appendStringInfo(es->str, " lossy=%ld", planstate->lossy_pages);
+               appendStringInfoChar(es->str, '\n');
+       }
+}
+
 /*
  * If it's EXPLAIN ANALYZE, show instrumentation information for a plan node
  *

diff --git a/src/backend/executor/nodeBitmapHeapscan.c b/src/backend/executor/nodeBitmapHeapscan.c
index 3d98c2335c17239b65fdba1d34b3ba0ebf7cba6c..1a8d4e51430b232d96080da14a3ecd781f2787d0 100644 (file)
--- a/src/backend/executor/nodeBitmapHeapscan.c
+++ b/src/backend/executor/nodeBitmapHeapscan.c
@@ -170,6 +170,11 @@ BitmapHeapNext(BitmapHeapScanState *node)
                         */
                        bitgetpage(scan, tbmres);
 
+                       if (tbmres->ntuples >= 0)
+                               node->exact_pages++;
+                       else
+                               node->lossy_pages++;
+
                        /*
                         * Set rs_cindex to first slot to examine
                         */
@@ -553,6 +558,8 @@ ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate, int eflags)
        scanstate->tbm = NULL;
        scanstate->tbmiterator = NULL;
        scanstate->tbmres = NULL;
+       scanstate->exact_pages = 0;
+       scanstate->lossy_pages = 0;
        scanstate->prefetch_iterator = NULL;
        scanstate->prefetch_pages = 0;
        scanstate->prefetch_target = 0;

diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 94ab0f2a93368dda4f3bf144a28a0bca20b317d9..a301a08fba9f1c532ce58a8ea8f2c7ea11511001 100644 (file)
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -1338,6 +1338,8 @@ typedef struct BitmapIndexScanState
  *             tbm                                bitmap obtained from child index scan(s)
  *             tbmiterator                iterator for scanning current pages
  *             tbmres                     current-page data
+ *             exact_pages                total number of exact pages retrieved
+ *             lossy_pages                total number of lossy pages retrieved
  *             prefetch_iterator  iterator for prefetching ahead of current page
  *             prefetch_pages     # pages prefetch iterator is ahead of current
  *             prefetch_target    target prefetch distance
@@ -1350,6 +1352,8 @@ typedef struct BitmapHeapScanState
        TIDBitmap  *tbm;
        TBMIterator *tbmiterator;
        TBMIterateResult *tbmres;
+       long            exact_pages;
+       long            lossy_pages;
        TBMIterator *prefetch_iterator;
        int                     prefetch_pages;
        int                     prefetch_target;