diff options
Diffstat (limited to 'src/backend/optimizer/path/allpaths.c')
| -rw-r--r-- | src/backend/optimizer/path/allpaths.c | 48 |
1 files changed, 20 insertions, 28 deletions
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c index 8b42e36b6d4..c97355e8fda 100644 --- a/src/backend/optimizer/path/allpaths.c +++ b/src/backend/optimizer/path/allpaths.c @@ -54,6 +54,9 @@ typedef struct pushdown_safety_info bool enable_geqo = false; /* just in case GUC doesn't set it */ int geqo_threshold; +/* Hook for plugins to get control in set_rel_pathlist() */ +set_rel_pathlist_hook_type set_rel_pathlist_hook = NULL; + /* Hook for plugins to replace standard_join_search() */ join_search_hook_type join_search_hook = NULL; @@ -355,6 +358,17 @@ set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, } } + /* + * Allow a plugin to editorialize on the set of Paths for this base + * relation. It could add new paths (such as CustomPaths) by calling + * add_path(), or delete or modify paths added by the core code. + */ + if (set_rel_pathlist_hook) + (*set_rel_pathlist_hook) (root, rel, rti, rte); + + /* Now find the cheapest of the paths for this rel */ + set_cheapest(rel); + #ifdef OPTIMIZER_DEBUG debug_print_rel(root, rel); #endif @@ -401,12 +415,6 @@ set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) /* Consider TID scans */ create_tidscan_paths(root, rel); - - /* Consider custom scans, if any */ - create_customscan_paths(root, rel, rte); - - /* Now find the cheapest of the paths for this rel */ - set_cheapest(rel); } /* @@ -432,9 +440,6 @@ set_foreign_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) { /* Call the FDW's GetForeignPaths function to generate path(s) */ rel->fdwroutine->GetForeignPaths(root, rel, rte->relid); - - /* Select cheapest path */ - set_cheapest(rel); } /* @@ -857,9 +862,6 @@ set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, add_path(rel, (Path *) create_append_path(rel, subpaths, required_outer)); } - - /* Select cheapest paths */ - set_cheapest(rel); } /* @@ -1087,7 +1089,12 @@ set_dummy_rel_pathlist(RelOptInfo *rel) add_path(rel, (Path *) create_append_path(rel, NIL, NULL)); - /* Select cheapest path (pretty easy in this case...) */ + /* + * We set the cheapest path immediately, to ensure that IS_DUMMY_REL() + * will recognize the relation as dummy if anyone asks. This is redundant + * when we're called from set_rel_size(), but not when called from + * elsewhere, and doing it twice is harmless anyway. + */ set_cheapest(rel); } @@ -1275,9 +1282,6 @@ set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel, /* Generate appropriate path */ add_path(rel, create_subqueryscan_path(root, rel, pathkeys, required_outer)); - - /* Select cheapest path (pretty easy in this case...) */ - set_cheapest(rel); } /* @@ -1346,9 +1350,6 @@ set_function_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) /* Generate appropriate path */ add_path(rel, create_functionscan_path(root, rel, pathkeys, required_outer)); - - /* Select cheapest path (pretty easy in this case...) */ - set_cheapest(rel); } /* @@ -1369,9 +1370,6 @@ set_values_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) /* Generate appropriate path */ add_path(rel, create_valuesscan_path(root, rel, required_outer)); - - /* Select cheapest path (pretty easy in this case...) */ - set_cheapest(rel); } /* @@ -1438,9 +1436,6 @@ set_cte_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) /* Generate appropriate path */ add_path(rel, create_ctescan_path(root, rel, required_outer)); - - /* Select cheapest path (pretty easy in this case...) */ - set_cheapest(rel); } /* @@ -1491,9 +1486,6 @@ set_worktable_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) /* Generate appropriate path */ add_path(rel, create_worktablescan_path(root, rel, required_outer)); - - /* Select cheapest path (pretty easy in this case...) */ - set_cheapest(rel); } /* |