diff options
Diffstat (limited to 'src/backend/optimizer/path/allpaths.c')
| -rw-r--r-- | src/backend/optimizer/path/allpaths.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c index 373d982c497..6e59451e558 100644 --- a/src/backend/optimizer/path/allpaths.c +++ b/src/backend/optimizer/path/allpaths.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.51 1999/07/24 23:21:08 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.52 1999/07/30 22:34:17 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -59,6 +59,9 @@ make_one_rel(Query *root, List *rels) if (levels_needed <= 0) return NULL; + /* + * Generate access paths for the base rels. + */ set_base_rel_pathlist(root, rels); if (levels_needed <= 1) @@ -73,8 +76,10 @@ make_one_rel(Query *root, List *rels) { /* - * This means that joins or sorts are required. set selectivities - * of clauses that have not been set by an index. + * This means that joins or sorts are required. Set selectivities + * of any clauses not yet set. (I think that this is redundant; + * set_base_rel_pathlist should have set them all already. But + * a scan to check that they are all set doesn't cost much...) */ set_rest_relselec(root, rels); @@ -131,11 +136,15 @@ set_base_rel_pathlist(Query *root, List *rels) set_cheapest(rel, rel->pathlist); - /* - * if there is a qualification of sequential scan the selec. value - * is not set -- so set it explicitly -- Sunita + /* Set the selectivity estimates for any restriction clauses that + * didn't get set as a byproduct of index-path selectivity estimation + * (see create_index_path()). */ set_rest_selec(root, rel->restrictinfo); + + /* Calculate the estimated size (post-restrictions) and tuple width + * for this base rel. This uses the restriction clause selectivities. + */ rel->size = compute_rel_size(rel); rel->width = compute_rel_width(rel); } |