Remove nrm_match parameter from fix_upper_expr

With the changes in the previous commit, we can now use exact
nullingrels matches in all cases when fixing up expressions of
upper-level plan nodes that are not joins.  Therefore, we can remove
the nrm_match parameter from fix_upper_expr(), along with the
corresponding field in fix_upper_expr_context.

Author: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs482_DFHzQ079ZPp6c8UvmFdz3Jj+4K8tVRu9g2Bw34NPA@mail.gmail.com

diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index ae29d59c78f71b2108b50e0438aea6e2744f4668..c95aaa6d85811019c17cd69a97d29e3fa395929f 100644 (file)
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -78,7 +78,6 @@ typedef struct
        indexed_tlist *subplan_itlist;
        int                     newvarno;
        int                     rtoffset;
-       NullingRelsMatch nrm_match;
        double          num_exec;
 } fix_upper_expr_context;
 
@@ -197,7 +196,6 @@ static Node *fix_upper_expr(PlannerInfo *root,
                                                        indexed_tlist *subplan_itlist,
                                                        int newvarno,
                                                        int rtoffset,
-                                                       NullingRelsMatch nrm_match,
                                                        double num_exec);
 static Node *fix_upper_expr_mutator(Node *node,
                                                                        fix_upper_expr_context *context);
@@ -1407,7 +1405,6 @@ set_indexonlyscan_references(PlannerInfo *root,
                                           index_itlist,
                                           INDEX_VAR,
                                           rtoffset,
-                                          NRM_EQUAL,
                                           NUM_EXEC_TLIST((Plan *) plan));
        plan->scan.plan.qual = (List *)
                fix_upper_expr(root,
@@ -1415,7 +1412,6 @@ set_indexonlyscan_references(PlannerInfo *root,
                                           index_itlist,
                                           INDEX_VAR,
                                           rtoffset,
-                                          NRM_EQUAL,
                                           NUM_EXEC_QUAL((Plan *) plan));
        plan->recheckqual = (List *)
                fix_upper_expr(root,
@@ -1423,7 +1419,6 @@ set_indexonlyscan_references(PlannerInfo *root,
                                           index_itlist,
                                           INDEX_VAR,
                                           rtoffset,
-                                          NRM_EQUAL,
                                           NUM_EXEC_QUAL((Plan *) plan));
        /* indexqual is already transformed to reference index columns */
        plan->indexqual = fix_scan_list(root, plan->indexqual,
@@ -1660,7 +1655,6 @@ set_foreignscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_TLIST((Plan *) fscan));
                fscan->scan.plan.qual = (List *)
                        fix_upper_expr(root,
@@ -1668,7 +1662,6 @@ set_foreignscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_QUAL((Plan *) fscan));
                fscan->fdw_exprs = (List *)
                        fix_upper_expr(root,
@@ -1676,7 +1669,6 @@ set_foreignscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_QUAL((Plan *) fscan));
                fscan->fdw_recheck_quals = (List *)
                        fix_upper_expr(root,
@@ -1684,7 +1676,6 @@ set_foreignscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_QUAL((Plan *) fscan));
                pfree(itlist);
                /* fdw_scan_tlist itself just needs fix_scan_list() adjustments */
@@ -1746,7 +1737,6 @@ set_customscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_TLIST((Plan *) cscan));
                cscan->scan.plan.qual = (List *)
                        fix_upper_expr(root,
@@ -1754,7 +1744,6 @@ set_customscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_QUAL((Plan *) cscan));
                cscan->custom_exprs = (List *)
                        fix_upper_expr(root,
@@ -1762,7 +1751,6 @@ set_customscan_references(PlannerInfo *root,
                                                   itlist,
                                                   INDEX_VAR,
                                                   rtoffset,
-                                                  NRM_EQUAL,
                                                   NUM_EXEC_QUAL((Plan *) cscan));
                pfree(itlist);
                /* custom_scan_tlist itself just needs fix_scan_list() adjustments */
@@ -2039,7 +2027,6 @@ set_hash_references(PlannerInfo *root, Plan *plan, int rtoffset)
                                           outer_itlist,
                                           OUTER_VAR,
                                           rtoffset,
-                                          NRM_EQUAL,
                                           NUM_EXEC_QUAL(plan));
 
        /* Hash doesn't project */
@@ -2447,15 +2434,14 @@ set_join_references(PlannerInfo *root, Join *join, int rtoffset)
                         * Vars or PHVs seen in the NestLoopParam expression have
                         * nullingrels that include exactly the outer-join relids that
                         * appear in the outer side's output and can null the respective
-                        * Var or PHV.  So we can use exact nullingrels matches for the
-                        * NestLoopParam expression.
+                        * Var or PHV.  Therefore, fix_upper_expr will not complain when
+                        * performing the nullingrels matches here.
                         */
                        nlp->paramval = (Var *) fix_upper_expr(root,
                                                                                                   (Node *) nlp->paramval,
                                                                                                   outer_itlist,
                                                                                                   OUTER_VAR,
                                                                                                   rtoffset,
-                                                                                                  NRM_EQUAL,
                                                                                                   NUM_EXEC_TLIST(outer_plan));
                        /* Check we replaced any PlaceHolderVar with simple Var */
                        if (!(IsA(nlp->paramval, Var) &&
@@ -2498,7 +2484,6 @@ set_join_references(PlannerInfo *root, Join *join, int rtoffset)
                                                                                           outer_itlist,
                                                                                           OUTER_VAR,
                                                                                           rtoffset,
-                                                                                          NRM_EQUAL,
                                                                                           NUM_EXEC_QUAL((Plan *) join));
        }
 
@@ -2603,7 +2588,6 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
                                                                                 subplan_itlist,
                                                                                 OUTER_VAR,
                                                                                 rtoffset,
-                                                                                NRM_EQUAL,
                                                                                 NUM_EXEC_TLIST(plan));
                }
                else
@@ -2612,7 +2596,6 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
                                                                         subplan_itlist,
                                                                         OUTER_VAR,
                                                                         rtoffset,
-                                                                        NRM_EQUAL,
                                                                         NUM_EXEC_TLIST(plan));
                tle = flatCopyTargetEntry(tle);
                tle->expr = (Expr *) newexpr;
@@ -2626,7 +2609,6 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
                                           subplan_itlist,
                                           OUTER_VAR,
                                           rtoffset,
-                                          NRM_EQUAL,
                                           NUM_EXEC_QUAL(plan));
 
        pfree(subplan_itlist);
@@ -3332,11 +3314,13 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
  * expensive, so we don't want to try it in the common case where the
  * subplan tlist is just a flattened list of Vars.)
  *
+ * When cross-checking the nullingrels of the subplan output Vars/PHVs, we
+ * always expect exact matches.
+ *
  * 'node': the tree to be fixed (a target item or qual)
  * 'subplan_itlist': indexed target list for subplan (or index)
  * 'newvarno': varno to use for Vars referencing tlist elements
  * 'rtoffset': how much to increment varnos by
- * 'nrm_match': as for search_indexed_tlist_for_var()
  * 'num_exec': estimated number of executions of expression
  *
  * The resulting tree is a copy of the original in which all Var nodes have
@@ -3349,7 +3333,6 @@ fix_upper_expr(PlannerInfo *root,
                           indexed_tlist *subplan_itlist,
                           int newvarno,
                           int rtoffset,
-                          NullingRelsMatch nrm_match,
                           double num_exec)
 {
        fix_upper_expr_context context;
@@ -3358,7 +3341,6 @@ fix_upper_expr(PlannerInfo *root,
        context.subplan_itlist = subplan_itlist;
        context.newvarno = newvarno;
        context.rtoffset = rtoffset;
-       context.nrm_match = nrm_match;
        context.num_exec = num_exec;
        return fix_upper_expr_mutator(node, &context);
 }
@@ -3378,7 +3360,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
                                                                                          context->subplan_itlist,
                                                                                          context->newvarno,
                                                                                          context->rtoffset,
-                                                                                         context->nrm_match);
+                                                                                         NRM_EQUAL);
                if (!newvar)
                        elog(ERROR, "variable not found in subplan target list");
                return (Node *) newvar;
@@ -3393,7 +3375,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
                        newvar = search_indexed_tlist_for_phv(phv,
                                                                                                  context->subplan_itlist,
                                                                                                  context->newvarno,
-                                                                                                 context->nrm_match);
+                                                                                                 NRM_EQUAL);
                        if (newvar)
                                return (Node *) newvar;
                }