diff options
Diffstat (limited to 'src/backend/optimizer/path/joinpath.c')
| -rw-r--r-- | src/backend/optimizer/path/joinpath.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/src/backend/optimizer/path/joinpath.c b/src/backend/optimizer/path/joinpath.c index 65f86194e15..fe0e4d7c201 100644 --- a/src/backend/optimizer/path/joinpath.c +++ b/src/backend/optimizer/path/joinpath.c @@ -491,12 +491,18 @@ sort_inner_and_outer(PlannerInfo *root, * explosion of mergejoin paths of dubious value. This interacts with * decisions elsewhere that also discriminate against mergejoins with * parameterized inputs; see comments in src/backend/optimizer/README. - * - * If unique-ification is requested, do it and then handle as a plain - * inner join. */ outer_path = outerrel->cheapest_total_path; inner_path = innerrel->cheapest_total_path; + + /* Punt if either rel has only parameterized paths */ + if (!outer_path || !inner_path) + return; + + /* + * If unique-ification is requested, do it and then handle as a plain + * inner join. + */ if (jointype == JOIN_UNIQUE_OUTER) { outer_path = (Path *) create_unique_path(root, outerrel, @@ -696,6 +702,10 @@ match_unsorted_outer(PlannerInfo *root, */ if (save_jointype == JOIN_UNIQUE_INNER) { + /* XXX for the moment, don't crash on LATERAL --- rethink this */ + if (inner_cheapest_total == NULL) + return; + inner_cheapest_total = (Path *) create_unique_path(root, innerrel, inner_cheapest_total, sjinfo); Assert(inner_cheapest_total); @@ -707,7 +717,7 @@ match_unsorted_outer(PlannerInfo *root, * enable_material is off or the path in question materializes its * output anyway. */ - if (enable_material && + if (enable_material && inner_cheapest_total != NULL && !ExecMaterializesOutput(inner_cheapest_total->pathtype)) matpath = (Path *) create_material_path(innerrel, inner_cheapest_total); @@ -735,6 +745,8 @@ match_unsorted_outer(PlannerInfo *root, * If we need to unique-ify the outer path, it's pointless to consider * any but the cheapest outer. (XXX we don't consider parameterized * outers, nor inners, for unique-ified cases. Should we?) + * + * XXX does nothing for LATERAL, rethink */ if (save_jointype == JOIN_UNIQUE_OUTER) { @@ -814,6 +826,10 @@ match_unsorted_outer(PlannerInfo *root, if (save_jointype == JOIN_UNIQUE_OUTER) continue; + /* Can't do anything else if inner has no unparameterized paths */ + if (!inner_cheapest_total) + continue; + /* Look for useful mergeclauses (if any) */ mergeclauses = find_mergeclauses_for_pathkeys(root, outerpath->pathkeys, @@ -1092,6 +1108,12 @@ hash_inner_and_outer(PlannerInfo *root, Path *cheapest_total_outer = outerrel->cheapest_total_path; Path *cheapest_total_inner = innerrel->cheapest_total_path; + /* Punt if either rel has only parameterized paths */ + if (!cheapest_startup_outer || + !cheapest_total_outer || + !cheapest_total_inner) + return; + /* Unique-ify if need be; we ignore parameterized possibilities */ if (jointype == JOIN_UNIQUE_OUTER) { |