database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-08-31 17:02:12 +03:00
Code Activity

Add support for index-only scans in GiST.

Browse Source 
This adds a new GiST opclass method, 'fetch', which is used to reconstruct
the original Datum from the value stored in the index. Also, the 'canreturn'
index AM interface function gains a new 'attno' argument. That makes it
possible to use index-only scans on a multi-column index where some of the
opclasses support index-only scans but some do not.

This patch adds support in the box and point opclasses. Other opclasses
can added later as follow-on patches (btree_gist would be particularly
interesting).

Anastasia Lubennikova, with additional fixes and modifications by me.
This commit is contained in:
Heikki Linnakangas
2015-03-26 19:12:00 +02:00
parent 8fa393a6d7
commit d04c8ed904
24 changed files with 575 additions and 73 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/access/index/indexam.c
View File

@@ -722,11 +722,14 @@ index_vacuum_cleanup(IndexVacuumInfo *info,
}
/* ----------------
* index_can_return - does index support index-only scans?
* index_can_return
*
* Does the index access method support index-only scans for the given
* column?
* ----------------
*/
bool
index_can_return(Relation indexRelation)
index_can_return(Relation indexRelation, int attno)
{
FmgrInfo *procedure;
@@ -738,8 +741,9 @@ index_can_return(Relation indexRelation)
GET_REL_PROCEDURE(amcanreturn);
return DatumGetBool(FunctionCall1(procedure,
PointerGetDatum(indexRelation)));
return DatumGetBool(FunctionCall2(procedure,
PointerGetDatum(indexRelation),
Int32GetDatum(attno)));
}
/* ----------------