From 8224de4f42ccf98e08db07b43d52fed72f962ebb Mon Sep 17 00:00:00 2001 From: Teodor Sigaev Date: Sat, 7 Apr 2018 23:00:39 +0300 Subject: 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 --- src/backend/optimizer/path/indxpath.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/backend/optimizer/path/indxpath.c') diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index ec3f60d3115..cc607dcdfaa 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -2162,7 +2162,7 @@ match_eclass_clauses_to_index(PlannerInfo *root, IndexOptInfo *index, if (!index->rel->has_eclass_joins) return; - for (indexcol = 0; indexcol < index->ncolumns; indexcol++) + for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++) { ec_member_matches_arg arg; List *clauses; -- cgit v1.2.3