1 files changed, 11 insertions, 169 deletions

diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 3c9d84f665a..727da333388 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -139,9 +139,6 @@ static void subquery_push_qual(Query *subquery,
 static void recurse_push_qual(Node *setOp, Query *topquery,
 				  RangeTblEntry *rte, Index rti, Node *qual);
 static void remove_unused_subquery_outputs(Query *subquery, RelOptInfo *rel);
-static bool apply_child_basequals(PlannerInfo *root, RelOptInfo *rel,
-					  RelOptInfo *childrel,
-					  RangeTblEntry *childRTE, AppendRelInfo *appinfo);
 
 
 /*
@@ -396,8 +393,9 @@ set_rel_size(PlannerInfo *root, RelOptInfo *rel,
 				else if (rte->relkind == RELKIND_PARTITIONED_TABLE)
 				{
 					/*
-					 * A partitioned table without any partitions is marked as
-					 * a dummy rel.
+					 * We could get here if asked to scan a partitioned table
+					 * with ONLY.  In that case we shouldn't scan any of the
+					 * partitions, so mark it as a dummy rel.
 					 */
 					set_dummy_rel_pathlist(rel);
 				}
@@ -946,8 +944,6 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
 	double	   *parent_attrsizes;
 	int			nattrs;
 	ListCell   *l;
-	Relids		live_children = NULL;
-	bool		did_pruning = false;
 
 	/* Guard against stack overflow due to overly deep inheritance tree. */
 	check_stack_depth();
@@ -966,21 +962,6 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
 		rel->partitioned_child_rels = list_make1_int(rti);
 
 	/*
-	 * If the partitioned relation has any baserestrictinfo quals then we
-	 * attempt to use these quals to prune away partitions that cannot
-	 * possibly contain any tuples matching these quals.  In this case we'll
-	 * store the relids of all partitions which could possibly contain a
-	 * matching tuple, and skip anything else in the loop below.
-	 */
-	if (enable_partition_pruning &&
-		rte->relkind == RELKIND_PARTITIONED_TABLE &&
-		rel->baserestrictinfo != NIL)
-	{
-		live_children = prune_append_rel_partitions(rel);
-		did_pruning = true;
-	}
-
-	/*
 	 * If this is a partitioned baserel, set the consider_partitionwise_join
 	 * flag; currently, we only consider partitionwise joins with the baserel
 	 * if its targetlist doesn't contain a whole-row Var.
@@ -1034,30 +1015,17 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
 		childrel = find_base_rel(root, childRTindex);
 		Assert(childrel->reloptkind == RELOPT_OTHER_MEMBER_REL);
 
-		if (did_pruning && !bms_is_member(appinfo->child_relid, live_children))
-		{
-			/* This partition was pruned; skip it. */
-			set_dummy_rel_pathlist(childrel);
+		/* We may have already proven the child to be dummy. */
+		if (IS_DUMMY_REL(childrel))
 			continue;
-		}
 
 		/*
 		 * We have to copy the parent's targetlist and quals to the child,
-		 * with appropriate substitution of variables.  If any constant false
-		 * or NULL clauses turn up, we can disregard the child right away. If
-		 * not, we can apply constraint exclusion with just the
-		 * baserestrictinfo quals.
+		 * with appropriate substitution of variables.  However, the
+		 * baserestrictinfo quals were already copied/substituted when the
+		 * child RelOptInfo was built.  So we don't need any additional setup
+		 * before applying constraint exclusion.
 		 */
-		if (!apply_child_basequals(root, rel, childrel, childRTE, appinfo))
-		{
-			/*
-			 * Some restriction clause reduced to constant FALSE or NULL after
-			 * substitution, so this child need not be scanned.
-			 */
-			set_dummy_rel_pathlist(childrel);
-			continue;
-		}
-
 		if (relation_excluded_by_constraints(root, childrel, childRTE))
 		{
 			/*
@@ -1069,7 +1037,8 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
 		}
 
 		/*
-		 * CE failed, so finish copying/modifying targetlist and join quals.
+		 * Constraint exclusion failed, so copy the parent's join quals and
+		 * targetlist to the child, with appropriate variable substitutions.
 		 *
 		 * NB: the resulting childrel->reltarget->exprs may contain arbitrary
 		 * expressions, which otherwise would not occur in a rel's targetlist.
@@ -3596,133 +3565,6 @@ generate_partitionwise_join_paths(PlannerInfo *root, RelOptInfo *rel)
 	list_free(live_children);
 }
 
-/*
- * apply_child_basequals
- *		Populate childrel's quals based on rel's quals, translating them using
- *		appinfo.
- *
- * If any of the resulting clauses evaluate to false or NULL, we return false
- * and don't apply any quals.  Caller can mark the relation as a dummy rel in
- * this case, since it needn't be scanned.
- *
- * If any resulting clauses evaluate to true, they're unnecessary and we don't
- * apply then.
- */
-static bool
-apply_child_basequals(PlannerInfo *root, RelOptInfo *rel,
-					  RelOptInfo *childrel, RangeTblEntry *childRTE,
-					  AppendRelInfo *appinfo)
-{
-	List	   *childquals;
-	Index		cq_min_security;
-	ListCell   *lc;
-
-	/*
-	 * The child rel's targetlist might contain non-Var expressions, which
-	 * means that substitution into the quals could produce opportunities for
-	 * const-simplification, and perhaps even pseudoconstant quals. Therefore,
-	 * transform each RestrictInfo separately to see if it reduces to a
-	 * constant or pseudoconstant.  (We must process them separately to keep
-	 * track of the security level of each qual.)
-	 */
-	childquals = NIL;
-	cq_min_security = UINT_MAX;
-	foreach(lc, rel->baserestrictinfo)
-	{
-		RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
-		Node	   *childqual;
-		ListCell   *lc2;
-
-		Assert(IsA(rinfo, RestrictInfo));
-		childqual = adjust_appendrel_attrs(root,
-										   (Node *) rinfo->clause,
-										   1, &appinfo);
-		childqual = eval_const_expressions(root, childqual);
-		/* check for flat-out constant */
-		if (childqual && IsA(childqual, Const))
-		{
-			if (((Const *) childqual)->constisnull ||
-				!DatumGetBool(((Const *) childqual)->constvalue))
-			{
-				/* Restriction reduces to constant FALSE or NULL */
-				return false;
-			}
-			/* Restriction reduces to constant TRUE, so drop it */
-			continue;
-		}
-		/* might have gotten an AND clause, if so flatten it */
-		foreach(lc2, make_ands_implicit((Expr *) childqual))
-		{
-			Node	   *onecq = (Node *) lfirst(lc2);
-			bool		pseudoconstant;
-
-			/* check for pseudoconstant (no Vars or volatile functions) */
-			pseudoconstant =
-				!contain_vars_of_level(onecq, 0) &&
-				!contain_volatile_functions(onecq);
-			if (pseudoconstant)
-			{
-				/* tell createplan.c to check for gating quals */
-				root->hasPseudoConstantQuals = true;
-			}
-			/* reconstitute RestrictInfo with appropriate properties */
-			childquals = lappend(childquals,
-								 make_restrictinfo((Expr *) onecq,
-												   rinfo->is_pushed_down,
-												   rinfo->outerjoin_delayed,
-												   pseudoconstant,
-												   rinfo->security_level,
-												   NULL, NULL, NULL));
-			/* track minimum security level among child quals */
-			cq_min_security = Min(cq_min_security, rinfo->security_level);
-		}
-	}
-
-	/*
-	 * In addition to the quals inherited from the parent, we might have
-	 * securityQuals associated with this particular child node. (Currently
-	 * this can only happen in appendrels originating from UNION ALL;
-	 * inheritance child tables don't have their own securityQuals, see
-	 * expand_inherited_rtentry().)	Pull any such securityQuals up into the
-	 * baserestrictinfo for the child.  This is similar to
-	 * process_security_barrier_quals() for the parent rel, except that we
-	 * can't make any general deductions from such quals, since they don't
-	 * hold for the whole appendrel.
-	 */
-	if (childRTE->securityQuals)
-	{
-		Index		security_level = 0;
-
-		foreach(lc, childRTE->securityQuals)
-		{
-			List	   *qualset = (List *) lfirst(lc);
-			ListCell   *lc2;
-
-			foreach(lc2, qualset)
-			{
-				Expr	   *qual = (Expr *) lfirst(lc2);
-
-				/* not likely that we'd see constants here, so no check */
-				childquals = lappend(childquals,
-									 make_restrictinfo(qual,
-													   true, false, false,
-													   security_level,
-													   NULL, NULL, NULL));
-				cq_min_security = Min(cq_min_security, security_level);
-			}
-			security_level++;
-		}
-		Assert(security_level <= root->qual_security_level);
-	}
-
-	/*
-	 * OK, we've got all the baserestrictinfo quals for this child.
-	 */
-	childrel->baserestrictinfo = childquals;
-	childrel->baserestrict_min_security = cq_min_security;
-
-	return true;
-}
 
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