diff options
| author | Teodor Sigaev <teodor@sigaev.ru> | 2018-04-07 23:00:39 +0300 |
|---|---|---|
| committer | Teodor Sigaev <teodor@sigaev.ru> | 2018-04-07 23:00:39 +0300 |
| commit | 8224de4f42ccf98e08db07b43d52fed72f962ebb (patch) | |
| tree | 0c4aae878e522178def568fcd2dd274233780f88 /src/backend/utils/adt/selfuncs.c | |
| parent | 01bb85169afadfe63e2f0e344ff671292080de7e (diff) | |
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
Diffstat (limited to 'src/backend/utils/adt/selfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index f998d859c1c..fe606d72798 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -4902,7 +4902,7 @@ examine_variable(PlannerInfo *root, Node *node, int varRelid, * should match has_unique_index(). */ if (index->unique && - index->ncolumns == 1 && + index->nkeycolumns == 1 && (index->indpred == NIL || index->predOK)) vardata->isunique = true; @@ -7053,7 +7053,7 @@ btcostestimate(PlannerInfo *root, IndexPath *path, double loop_count, * NullTest invalidates that theory, even though it sets eqQualHere. */ if (index->unique && - indexcol == index->ncolumns - 1 && + indexcol == index->nkeycolumns - 1 && eqQualHere && !found_saop && !found_is_null_op) |