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| 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/include/parser | |
| parent | 01bb85169afadfe63e2f0e344ff671292080de7e (diff) | |
| download | postgresql-8224de4f42ccf98e08db07b43d52fed72f962ebb.tar.gz postgresql-8224de4f42ccf98e08db07b43d52fed72f962ebb.zip | |
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/include/parser')
| -rw-r--r-- | src/include/parser/kwlist.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h index 4dff55a8e99..81f758afbf0 100644 --- a/src/include/parser/kwlist.h +++ b/src/include/parser/kwlist.h @@ -196,6 +196,7 @@ PG_KEYWORD("immutable", IMMUTABLE, UNRESERVED_KEYWORD) PG_KEYWORD("implicit", IMPLICIT_P, UNRESERVED_KEYWORD) PG_KEYWORD("import", IMPORT_P, UNRESERVED_KEYWORD) PG_KEYWORD("in", IN_P, RESERVED_KEYWORD) +PG_KEYWORD("include", INCLUDE, UNRESERVED_KEYWORD) PG_KEYWORD("including", INCLUDING, UNRESERVED_KEYWORD) PG_KEYWORD("increment", INCREMENT, UNRESERVED_KEYWORD) PG_KEYWORD("index", INDEX, UNRESERVED_KEYWORD) |