diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2009-03-26 17:15:35 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2009-03-26 17:15:35 +0000 |
| commit | f38fbf31f5719bb84b18042a7f415a4f20db2bfa (patch) | |
| tree | 9de323400560bd677e4402727b1f6bb3ec9834e9 /src/backend/optimizer/path/costsize.c | |
| parent | ee4c187f6471af5f71fd5dd12021fa8d7c4fce11 (diff) | |
| download | postgresql-f38fbf31f5719bb84b18042a7f415a4f20db2bfa.tar.gz postgresql-f38fbf31f5719bb84b18042a7f415a4f20db2bfa.zip | |
If we expect a hash join to be performed in multiple batches, suppress
"physical tlist" optimization on the outer relation (ie, force a projection
step to occur in its scan). This avoids storing useless column values when
the outer relation's tuples are written to temporary batch files.
Modified version of a patch by Michael Henderson and Ramon Lawrence.
Diffstat (limited to 'src/backend/optimizer/path/costsize.c')
| -rw-r--r-- | src/backend/optimizer/path/costsize.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c index b07a2599bbe..2b3cf61e751 100644 --- a/src/backend/optimizer/path/costsize.c +++ b/src/backend/optimizer/path/costsize.c @@ -54,7 +54,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.205 2009/03/21 00:04:39 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.206 2009/03/26 17:15:35 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1880,6 +1880,8 @@ cost_hashjoin(HashPath *path, PlannerInfo *root, SpecialJoinInfo *sjinfo) &numbatches, &num_skew_mcvs); virtualbuckets = (double) numbuckets *(double) numbatches; + /* mark the path with estimated # of batches */ + path->num_batches = numbatches; /* * Determine bucketsize fraction for inner relation. We use the smallest |