Indexes with INCLUDE columns and their support in B-tree

This patch introduces INCLUDE clause to index definition.  This clause
specifies a list of columns which will be included as a non-key part in
the index.  The INCLUDE columns exist solely to allow more queries to
benefit from index-only scans.  Also, such columns don't need to have
appropriate operator classes.  Expressions are not supported as INCLUDE
columns since they cannot be used in index-only scans.

Index access methods supporting INCLUDE are indicated by amcaninclude flag
in IndexAmRoutine.  For now, only B-tree indexes support INCLUDE clause.

In B-tree indexes INCLUDE columns are truncated from pivot index tuples
(tuples located in non-leaf pages and high keys).  Therefore, B-tree indexes
now might have variable number of attributes.  This patch also provides
generic facility to support that: pivot tuples contain number of their
attributes in t_tid.ip_posid.  Free 13th bit of t_info is used for indicating
that.  This facility will simplify further support of index suffix truncation.
The changes of above are backward-compatible, pg_upgrade doesn't need special
handling of B-tree indexes for that.

Bump catalog version

Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me
Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes,
			 David Rowley, Alexander Korotkov
Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru

1 files changed, 3 insertions, 3 deletions

diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c
index 971f92a938a..6c5a5401c32 100644
--- a/src/backend/executor/execReplication.c
+++ b/src/backend/executor/execReplication.c
@@ -63,7 +63,7 @@ build_replindex_scan_key(ScanKey skey, Relation rel, Relation idxrel,
 	opclass = (oidvector *) DatumGetPointer(indclassDatum);
 
 	/* Build scankey for every attribute in the index. */
-	for (attoff = 0; attoff < RelationGetNumberOfAttributes(idxrel); attoff++)
+	for (attoff = 0; attoff < IndexRelationGetNumberOfKeyAttributes(idxrel); attoff++)
 	{
 		Oid			operator;
 		Oid			opfamily;
@@ -131,7 +131,7 @@ RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
 	/* Start an index scan. */
 	InitDirtySnapshot(snap);
 	scan = index_beginscan(rel, idxrel, &snap,
-						   RelationGetNumberOfAttributes(idxrel),
+						   IndexRelationGetNumberOfKeyAttributes(idxrel),
 						   0);
 
 	/* Build scan key. */
@@ -140,7 +140,7 @@ RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
 retry:
 	found = false;
 
-	index_rescan(scan, skey, RelationGetNumberOfAttributes(idxrel), NULL, 0);
+	index_rescan(scan, skey, IndexRelationGetNumberOfKeyAttributes(idxrel), NULL, 0);
 
 	/* Try to find the tuple */
 	if ((scantuple = index_getnext(scan, ForwardScanDirection)) != NULL)