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/[email protected]

1 files changed, 2 insertions, 0 deletions

diff --git a/src/backend/bootstrap/bootparse.y b/src/backend/bootstrap/bootparse.y
index 4ea3aa97cf7..1ec0e5c8a9c 100644
--- a/src/backend/bootstrap/bootparse.y
+++ b/src/backend/bootstrap/bootparse.y
@@ -302,6 +302,7 @@ Boot_DeclareIndexStmt:
 					stmt->accessMethod = $8;
 					stmt->tableSpace = NULL;
 					stmt->indexParams = $10;
+					stmt->indexIncludingParams = NIL;
 					stmt->options = NIL;
 					stmt->whereClause = NULL;
 					stmt->excludeOpNames = NIL;
@@ -350,6 +351,7 @@ Boot_DeclareUniqueIndexStmt:
 					stmt->accessMethod = $9;
 					stmt->tableSpace = NULL;
 					stmt->indexParams = $11;
+					stmt->indexIncludingParams = NIL;
 					stmt->options = NIL;
 					stmt->whereClause = NULL;
 					stmt->excludeOpNames = NIL;