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| author | Alexander Korotkov <akorotkov@postgresql.org> | 2019-03-10 11:36:47 +0300 |
|---|---|---|
| committer | Alexander Korotkov <akorotkov@postgresql.org> | 2019-03-10 11:37:17 +0300 |
| commit | f2e403803fe6deb8cff59ea09dff42c6163b2110 (patch) | |
| tree | 1c3afef6e11f6498002b88219d9644e71bb5972d /src/backend/access/gist/gistscan.c | |
| parent | a0b762626884b3b949c2703abb1c4b42fbbdfdc6 (diff) | |
| download | postgresql-f2e403803fe6deb8cff59ea09dff42c6163b2110.tar.gz postgresql-f2e403803fe6deb8cff59ea09dff42c6163b2110.zip | |
Support for INCLUDE attributes in GiST indexes
Similarly to B-tree, GiST index access method gets support of INCLUDE
attributes. These attributes aren't used for tree navigation and aren't
present in non-leaf pages. But they are present in leaf pages and can be
fetched during index-only scan.
The point of having INCLUDE attributes in GiST indexes is slightly different
from the point of having them in B-tree. The main point of INCLUDE attributes
in B-tree is to define UNIQUE constraint over part of attributes enabled for
index-only scan. In GiST the main point of INCLUDE attributes is to use
index-only scan for attributes, whose data types don't have GiST opclasses.
Discussion: https://postgr.es/m/73A1A452-AD5F-40D4-BD61-978622FF75C1%40yandex-team.ru
Author: Andrey Borodin, with small changes by me
Reviewed-by: Andreas Karlsson
Diffstat (limited to 'src/backend/access/gist/gistscan.c')
| -rw-r--r-- | src/backend/access/gist/gistscan.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c index 78a8ede7949..893d7765b6c 100644 --- a/src/backend/access/gist/gistscan.c +++ b/src/backend/access/gist/gistscan.c @@ -158,6 +158,7 @@ gistrescan(IndexScanDesc scan, ScanKey key, int nkeys, if (scan->xs_want_itup && !scan->xs_hitupdesc) { int natts; + int nkeyatts; int attno; /* @@ -167,13 +168,23 @@ gistrescan(IndexScanDesc scan, ScanKey key, int nkeys, * types. */ natts = RelationGetNumberOfAttributes(scan->indexRelation); + nkeyatts = IndexRelationGetNumberOfKeyAttributes(scan->indexRelation); so->giststate->fetchTupdesc = CreateTemplateTupleDesc(natts); - for (attno = 1; attno <= natts; attno++) + for (attno = 1; attno <= nkeyatts; attno++) { TupleDescInitEntry(so->giststate->fetchTupdesc, attno, NULL, scan->indexRelation->rd_opcintype[attno - 1], -1, 0); } + + for (; attno <= natts; attno++) + { + /* taking opcintype from giststate->tupdesc */ + TupleDescInitEntry(so->giststate->fetchTupdesc, attno, NULL, + TupleDescAttr(so->giststate->leafTupdesc, + attno - 1)->atttypid, + -1, 0); + } scan->xs_hitupdesc = so->giststate->fetchTupdesc; /* Also create a memory context that will hold the returned tuples */ |