Fix up pgstats counting of live and dead tuples to recognize that committed

and aborted transactions have different effects; also teach it not to assume
that prepared transactions are always committed.

Along the way, simplify the pgstats API by tying counting directly to
Relations; I cannot detect any redeeming social value in having stats
pointers in HeapScanDesc and IndexScanDesc structures.  And fix a few
corner cases in which counts might be missed because the relation's
pgstat_info pointer hadn't been set.

1 files changed, 5 insertions, 7 deletions

diff --git a/src/backend/access/index/indexam.c b/src/backend/access/index/indexam.c
index 23522ba740e..d905013a5fc 100644
--- a/src/backend/access/index/indexam.c
+++ b/src/backend/access/index/indexam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.97 2007/01/05 22:19:23 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.98 2007/05/27 03:50:38 tgl Exp $
  *
  * INTERFACE ROUTINES
  *		index_open		- open an index relation by relation OID
@@ -145,8 +145,6 @@ index_open(Oid relationId, LOCKMODE lockmode)
 				 errmsg("\"%s\" is not an index",
 						RelationGetRelationName(r))));
 
-	pgstat_initstats(&r->pgstat_info, r);
-
 	return r;
 }
 
@@ -433,14 +431,14 @@ index_getnext(IndexScanDesc scan, ScanDirection direction)
 			return NULL;		/* failure exit */
 		}
 
-		pgstat_count_index_tuples(&scan->xs_pgstat_info, 1);
+		pgstat_count_index_tuples(scan->indexRelation, 1);
 
 		/*
 		 * Fetch the heap tuple and see if it matches the snapshot.
 		 */
 		if (heap_release_fetch(scan->heapRelation, scan->xs_snapshot,
 							   heapTuple, &scan->xs_cbuf, true,
-							   &scan->xs_pgstat_info))
+							   scan->indexRelation))
 			break;
 
 		/* Skip if no undeleted tuple at this location */
@@ -502,7 +500,7 @@ index_getnext_indexitem(IndexScanDesc scan,
 									   Int32GetDatum(direction)));
 
 	if (found)
-		pgstat_count_index_tuples(&scan->xs_pgstat_info, 1);
+		pgstat_count_index_tuples(scan->indexRelation, 1);
 
 	return found;
 }
@@ -543,7 +541,7 @@ index_getmulti(IndexScanDesc scan,
 									   Int32GetDatum(max_tids),
 									   PointerGetDatum(returned_tids)));
 
-	pgstat_count_index_tuples(&scan->xs_pgstat_info, *returned_tids);
+	pgstat_count_index_tuples(scan->indexRelation, *returned_tids);
 
 	return found;
 }