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Indexes with INCLUDE columns and their support in B-tree

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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
This commit is contained in:
Teodor Sigaev
2018-04-07 23:00:39 +03:00
parent 01bb85169a
commit 8224de4f42
89 changed files with 2112 additions and 467 deletions
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6
src/backend/executor/execReplication.c
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@@ -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)