index cd3fdd259cdccb0be776c5d769bca4bc616caa7e..d73ac562eb9ad8849aed570f30010a6d84175c84 100644 (file)
@@ -3019,10 +3019,11 @@ standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
join_search_one_level(root, lev);
/*
- * Run generate_partitionwise_join_paths() and generate_gather_paths()
- * for each just-processed joinrel. We could not do this earlier
- * because both regular and partial paths can get added to a
- * particular joinrel at multiple times within join_search_one_level.
+ * Run generate_partitionwise_join_paths() and
+ * generate_useful_gather_paths() for each just-processed joinrel. We
+ * could not do this earlier because both regular and partial paths
+ * can get added to a particular joinrel at multiple times within
+ * join_search_one_level.
*
* After that, we're done creating paths for the joinrel, so run
* set_cheapest().
index adf68d8790689588c8e24c32d853774980ce471e..545b56bcafd53f3654abd17d099a45db3cc8abdf 100644 (file)
* Generate Gather and Gather Merge paths for a grouping relation or partial
* grouping relation.
*
- * generate_gather_paths does most of the work, but we also consider a special
- * case: we could try sorting the data by the group_pathkeys and then applying
- * Gather Merge.
+ * generate_useful_gather_paths does most of the work, but we also consider a
+ * special case: we could try sorting the data by the group_pathkeys and then
+ * applying Gather Merge.
*
* NB: This function shouldn't be used for anything other than a grouped or
* partially grouped relation not only because of the fact that it explicitly
* references group_pathkeys but we pass "true" as the third argument to
- * generate_gather_paths().
+ * generate_useful_gather_paths().
*/
static void
gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel)
* variations. So we drop old paths and thereby force the work to be done
* below the Append, except in the case of a non-parallel-safe target.
*
- * Some care is needed, because we have to allow generate_gather_paths to
- * see the old partial paths in the next stanza. Hence, zap the main
- * pathlist here, then allow generate_gather_paths to add path(s) to the
- * main list, and finally zap the partial pathlist.
+ * Some care is needed, because we have to allow
+ * generate_useful_gather_paths to see the old partial paths in the next
+ * stanza. Hence, zap the main pathlist here, then allow
+ * generate_useful_gather_paths to add path(s) to the main list, and
+ * finally zap the partial pathlist.
*/
if (rel_is_partitioned)
rel->pathlist = NIL;