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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2002-11-24 21:52:15 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2002-11-24 21:52:15 +0000 |
| commit | 04c8785c7b2b3dea038522cd96085c710c628c5b (patch) | |
| tree | 728c137a49ae2c3e02a8c00b549543ab23680b75 /src/backend/optimizer/util/pathnode.c | |
| parent | 6bfc09baf4043a6b9db9a4bae245973e7557998e (diff) | |
| download | postgresql-04c8785c7b2b3dea038522cd96085c710c628c5b.tar.gz postgresql-04c8785c7b2b3dea038522cd96085c710c628c5b.zip | |
Restructure planning of nestloop inner indexscans so that the set of usable
joinclauses is determined accurately for each join. Formerly, the code only
considered joinclauses that used all of the rels from the outer side of the
join; thus for example
FROM (a CROSS JOIN b) JOIN c ON (c.f1 = a.x AND c.f2 = b.y)
could not exploit a two-column index on c(f1,f2), since neither of the
qual clauses would be in the joininfo list it looked in. The new code does
this correctly, and also is able to eliminate redundant clauses, thus fixing
the problem noted 24-Oct-02 by Hans-Jürgen Schönig.
Diffstat (limited to 'src/backend/optimizer/util/pathnode.c')
| -rw-r--r-- | src/backend/optimizer/util/pathnode.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c index 7dd0dce6891..e99435a6edf 100644 --- a/src/backend/optimizer/util/pathnode.c +++ b/src/backend/optimizer/util/pathnode.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.79 2002/11/06 00:00:44 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/optimizer/util/pathnode.c,v 1.80 2002/11/24 21:52:14 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -354,12 +354,9 @@ create_index_path(Query *root, pathnode->indexscandir = indexscandir; /* - * This routine is only used to generate "standalone" indexpaths, not - * nestloop inner indexpaths. So joinrelids is always NIL and the - * number of rows is the same as the parent rel's estimate. + * The number of rows is the same as the parent rel's estimate, since + * this isn't a join inner indexscan. */ - pathnode->joinrelids = NIL; /* no join clauses here */ - pathnode->alljoinquals = false; pathnode->rows = rel->rows; /* |