remove grouping_distribution(), obsoleted by the pathification

The function was injecting Plan node (RemoteSubplan), but that
is incompatible with the pathified planner approach. The new
code uses grouping_distribution_match(), which only checks that
the grouping and distributions are compatible.

diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index cb150c01bdd231cc30c85294a73ba214866a6689..bfeb12e335a1afd2b6500c6773554fce5b343f0c 100644 (file)
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -155,18 +155,13 @@ static PathTarget *make_window_input_target(PlannerInfo *root,
                                                 List *activeWindows);
 static List *make_pathkeys_for_window(PlannerInfo *root, WindowClause *wc,
                                                 List *tlist);
-#ifdef XCP
-static Plan *grouping_distribution(PlannerInfo *root, Plan *plan,
-                                         int numGroupCols, AttrNumber *groupColIdx,
-                                         List *current_pathkeys, Distribution **distribution);
+static PathTarget *make_sort_input_target(PlannerInfo *root,
+                                          PathTarget *final_target,
+                                          bool *have_postponed_srfs);
 static bool equal_distributions(PlannerInfo *root, Distribution *dst1,
                                        Distribution *dst2);
 static bool grouping_distribution_match(PlannerInfo *root, Path *path,
                                          Query *parse);
-#endif
-static PathTarget *make_sort_input_target(PlannerInfo *root,
-                                          PathTarget *final_target,
-                                          bool *have_postponed_srfs);
 
 
 /*****************************************************************************
@@ -5618,7 +5613,6 @@ plan_cluster_use_sort(Oid tableOid, Oid indexOid)
 }
 
 
-#ifdef XCP
 static bool
 grouping_distribution_match(PlannerInfo *root, Path *path, Query *parse)
 {
@@ -5664,43 +5658,6 @@ grouping_distribution_match(PlannerInfo *root, Path *path, Query *parse)
 }
 
 /*
- * Grouping preserves distribution if distribution key is the
- * first grouping key or if distribution is replicated.
- * In these cases aggregation is fully pushed down to nodes.
- * Otherwise we need 2-phase aggregation so put remote subplan
- * on top of the result_plan. When adding result agg on top of
- * RemoteSubplan first aggregation phase will be pushed down
- * automatically.
- */
-static Plan *
-grouping_distribution(PlannerInfo *root, Plan *plan,
-                                         int numGroupCols, AttrNumber *groupColIdx,
-                                         List *current_pathkeys, Distribution **distribution)
-{
-       if (*distribution &&
-                       !IsLocatorReplicated((*distribution)->distributionType) &&
-                       (numGroupCols == 0 ||
-                                       (*distribution)->distributionExpr == NULL ||
-                                       !equal(((TargetEntry *)list_nth(plan->targetlist, groupColIdx[0]-1))->expr,
-                                                  (*distribution)->distributionExpr)))
-       {
-               Plan *result_plan;
-               result_plan = (Plan *) make_remotesubplan(root, plan, NULL,
-                                                                                                 *distribution,
-                                                                                                 current_pathkeys);
-               *distribution = NULL;
-               return result_plan;
-       }
-       return plan;
-}
-
-
-/*
- * Check if two distributions are equal.
- * Distributions are considered equal if they are of the same type, on the same
- * nodes and if they have distribution expressions defined they are equal
- * (either the same expressions or they are member of the same equivalence
- * class)
  */
 static bool
 equal_distributions(PlannerInfo *root, Distribution *dst1,
@@ -5741,4 +5698,3 @@ equal_distributions(PlannerInfo *root, Distribution *dst1,
        /* The restrictNodes field does not matter for distribution equality */
        return false;
 }
-#endif