X-Git-Url: https://granicus.if.org/sourcecode?a=blobdiff_plain;f=src%2Fbackend%2Foptimizer%2Fpath%2Fallpaths.c;h=f6fffec902e74f3b6373c2ee8c54926296277c92;hb=0adaf4cb312fe3eff83e786d6a0b53ae2cdc9302;hp=6c40a16e32a779265adddbd90040ebfc53464968;hpb=9f5f2124754ccd605671bfe952c220b46a0e730b;p=postgresql

diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 6c40a16e32..f6fffec902 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -3,18 +3,21 @@
  * allpaths.c
  *	  Routines to find possible search paths for processing a query
  *
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.95 2003/01/25 23:10:27 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.187 2009/10/12 18:10:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 
 #include "postgres.h"
 
+#include <math.h>
+
+#include "nodes/nodeFuncs.h"
 #ifdef OPTIMIZER_DEBUG
 #include "nodes/print.h"
 #endif
@@ -26,6 +29,9 @@
 #include "optimizer/plancat.h"
 #include "optimizer/planner.h"
 #include "optimizer/prep.h"
+#include "optimizer/restrictinfo.h"
+#include "optimizer/var.h"
+#include "parser/parse_clause.h"
 #include "parser/parsetree.h"
 #include "rewrite/rewriteManip.h"
 
@@ -34,24 +40,41 @@
 bool		enable_geqo = false;	/* just in case GUC doesn't set it */
 int			geqo_threshold;
 
+/* Hook for plugins to replace standard_join_search() */
+join_search_hook_type join_search_hook = NULL;
+
 
-static void set_base_rel_pathlists(Query *root);
-static void set_plain_rel_pathlist(Query *root, RelOptInfo *rel,
+static void set_base_rel_pathlists(PlannerInfo *root);
+static void set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
+				 Index rti, RangeTblEntry *rte);
+static void set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					   RangeTblEntry *rte);
-static void set_inherited_rel_pathlist(Query *root, RelOptInfo *rel,
-						   Index rti, RangeTblEntry *rte,
-						   List *inheritlist);
-static void set_subquery_pathlist(Query *root, RelOptInfo *rel,
+static void set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
+						Index rti, RangeTblEntry *rte);
+static void set_dummy_rel_pathlist(RelOptInfo *rel);
+static void set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					  Index rti, RangeTblEntry *rte);
-static void set_function_pathlist(Query *root, RelOptInfo *rel,
+static void set_function_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					  RangeTblEntry *rte);
-static RelOptInfo *make_one_rel_by_joins(Query *root, int levels_needed,
-					  List *initial_rels);
-static bool subquery_is_pushdown_safe(Query *subquery, Query *topquery);
-static bool recurse_pushdown_safe(Node *setOp, Query *topquery);
-static void subquery_push_qual(Query *subquery, Index rti, Node *qual);
+static void set_values_pathlist(PlannerInfo *root, RelOptInfo *rel,
+					RangeTblEntry *rte);
+static void set_cte_pathlist(PlannerInfo *root, RelOptInfo *rel,
+				 RangeTblEntry *rte);
+static void set_worktable_pathlist(PlannerInfo *root, RelOptInfo *rel,
+					   RangeTblEntry *rte);
+static RelOptInfo *make_rel_from_joinlist(PlannerInfo *root, List *joinlist);
+static bool subquery_is_pushdown_safe(Query *subquery, Query *topquery,
+						  bool *differentTypes);
+static bool recurse_pushdown_safe(Node *setOp, Query *topquery,
+					  bool *differentTypes);
+static void compare_tlist_datatypes(List *tlist, List *colTypes,
+						bool *differentTypes);
+static bool qual_is_pushdown_safe(Query *subquery, Index rti, Node *qual,
+					  bool *differentTypes);
+static void subquery_push_qual(Query *subquery,
+				   RangeTblEntry *rte, Index rti, Node *qual);
 static void recurse_push_qual(Node *setOp, Query *topquery,
-				  Index rti, Node *qual);
+				  RangeTblEntry *rte, Index rti, Node *qual);
 
 
 /*
@@ -60,7 +83,7 @@ static void recurse_push_qual(Node *setOp, Query *topquery,
  *	  single rel that represents the join of all base rels in the query.
  */
 RelOptInfo *
-make_one_rel(Query *root)
+make_one_rel(PlannerInfo *root, List *joinlist)
 {
 	RelOptInfo *rel;
 
@@ -72,14 +95,36 @@ make_one_rel(Query *root)
 	/*
 	 * Generate access paths for the entire join tree.
 	 */
-	Assert(root->jointree != NULL && IsA(root->jointree, FromExpr));
-
-	rel = make_fromexpr_rel(root, root->jointree);
+	rel = make_rel_from_joinlist(root, joinlist);
 
 	/*
-	 * The result should join all the query's base rels.
+	 * The result should join all and only the query's base rels.
 	 */
-	Assert(length(rel->relids) == length(root->base_rel_list));
+#ifdef USE_ASSERT_CHECKING
+	{
+		int			num_base_rels = 0;
+		Index		rti;
+
+		for (rti = 1; rti < root->simple_rel_array_size; rti++)
+		{
+			RelOptInfo *brel = root->simple_rel_array[rti];
+
+			if (brel == NULL)
+				continue;
+
+			Assert(brel->relid == rti); /* sanity check on array */
+
+			/* ignore RTEs that are "other rels" */
+			if (brel->reloptkind != RELOPT_BASEREL)
+				continue;
+
+			Assert(bms_is_member(rti, rel->relids));
+			num_base_rels++;
+		}
+
+		Assert(bms_num_members(rel->relids) == num_base_rels);
+	}
+#endif
 
 	return rel;
 }
@@ -91,47 +136,74 @@ make_one_rel(Query *root)
  *	  Each useful path is attached to its relation's 'pathlist' field.
  */
 static void
-set_base_rel_pathlists(Query *root)
+set_base_rel_pathlists(PlannerInfo *root)
 {
-	List	   *rellist;
+	Index		rti;
 
-	foreach(rellist, root->base_rel_list)
+	for (rti = 1; rti < root->simple_rel_array_size; rti++)
 	{
-		RelOptInfo *rel = (RelOptInfo *) lfirst(rellist);
-		Index		rti;
-		RangeTblEntry *rte;
-		List	   *inheritlist;
+		RelOptInfo *rel = root->simple_rel_array[rti];
 
-		Assert(length(rel->relids) == 1);		/* better be base rel */
-		rti = lfirsti(rel->relids);
-		rte = rt_fetch(rti, root->rtable);
+		/* there may be empty slots corresponding to non-baserel RTEs */
+		if (rel == NULL)
+			continue;
 
-		if (rel->rtekind == RTE_SUBQUERY)
-		{
-			/* Subquery --- generate a separate plan for it */
-			set_subquery_pathlist(root, rel, rti, rte);
-		}
-		else if (rel->rtekind == RTE_FUNCTION)
-		{
-			/* RangeFunction --- generate a separate plan for it */
-			set_function_pathlist(root, rel, rte);
-		}
-		else if ((inheritlist = expand_inherted_rtentry(root, rti, true))
-				 != NIL)
-		{
-			/* Relation is root of an inheritance tree, process specially */
-			set_inherited_rel_pathlist(root, rel, rti, rte, inheritlist);
-		}
+		Assert(rel->relid == rti);		/* sanity check on array */
+
+		/* ignore RTEs that are "other rels" */
+		if (rel->reloptkind != RELOPT_BASEREL)
+			continue;
+
+		set_rel_pathlist(root, rel, rti, root->simple_rte_array[rti]);
+	}
+}
+
+/*
+ * set_rel_pathlist
+ *	  Build access paths for a base relation
+ */
+static void
+set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
+				 Index rti, RangeTblEntry *rte)
+{
+	if (rte->inh)
+	{
+		/* It's an "append relation", process accordingly */
+		set_append_rel_pathlist(root, rel, rti, rte);
+	}
+	else if (rel->rtekind == RTE_SUBQUERY)
+	{
+		/* Subquery --- generate a separate plan for it */
+		set_subquery_pathlist(root, rel, rti, rte);
+	}
+	else if (rel->rtekind == RTE_FUNCTION)
+	{
+		/* RangeFunction --- generate a suitable path for it */
+		set_function_pathlist(root, rel, rte);
+	}
+	else if (rel->rtekind == RTE_VALUES)
+	{
+		/* Values list --- generate a suitable path for it */
+		set_values_pathlist(root, rel, rte);
+	}
+	else if (rel->rtekind == RTE_CTE)
+	{
+		/* CTE reference --- generate a suitable path for it */
+		if (rte->self_reference)
+			set_worktable_pathlist(root, rel, rte);
 		else
-		{
-			/* Plain relation */
-			set_plain_rel_pathlist(root, rel, rte);
-		}
+			set_cte_pathlist(root, rel, rte);
+	}
+	else
+	{
+		/* Plain relation */
+		Assert(rel->rtekind == RTE_RELATION);
+		set_plain_rel_pathlist(root, rel, rte);
+	}
 
 #ifdef OPTIMIZER_DEBUG
-		debug_print_rel(root, rel);
+	debug_print_rel(root, rel);
 #endif
-	}
 }
 
 /*
@@ -139,11 +211,41 @@ set_base_rel_pathlists(Query *root)
  *	  Build access paths for a plain relation (no subquery, no inheritance)
  */
 static void
-set_plain_rel_pathlist(Query *root, RelOptInfo *rel, RangeTblEntry *rte)
+set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
 {
+	/*
+	 * If we can prove we don't need to scan the rel via constraint exclusion,
+	 * set up a single dummy path for it.  We only need to check for regular
+	 * baserels; if it's an otherrel, CE was already checked in
+	 * set_append_rel_pathlist().
+	 */
+	if (rel->reloptkind == RELOPT_BASEREL &&
+		relation_excluded_by_constraints(root, rel, rte))
+	{
+		set_dummy_rel_pathlist(rel);
+		return;
+	}
+
+	/*
+	 * Test any partial indexes of rel for applicability.  We must do this
+	 * first since partial unique indexes can affect size estimates.
+	 */
+	check_partial_indexes(root, rel);
+
 	/* Mark rel with estimated output rows, width, etc */
 	set_baserel_size_estimates(root, rel);
 
+	/*
+	 * Check to see if we can extract any restriction conditions from join
+	 * quals that are OR-of-AND structures.  If so, add them to the rel's
+	 * restriction list, and redo the above steps.
+	 */
+	if (create_or_index_quals(root, rel))
+	{
+		check_partial_indexes(root, rel);
+		set_baserel_size_estimates(root, rel);
+	}
+
 	/*
 	 * Generate paths and add them to the rel's pathlist.
 	 *
@@ -155,127 +257,235 @@ set_plain_rel_pathlist(Query *root, RelOptInfo *rel, RangeTblEntry *rte)
 	/* Consider sequential scan */
 	add_path(rel, create_seqscan_path(root, rel));
 
-	/* Consider TID scans */
-	create_tidscan_paths(root, rel);
-
-	/* Consider index paths for both simple and OR index clauses */
+	/* Consider index scans */
 	create_index_paths(root, rel);
 
-	/* create_index_paths must be done before create_or_index_paths */
-	create_or_index_paths(root, rel);
+	/* Consider TID scans */
+	create_tidscan_paths(root, rel);
 
 	/* Now find the cheapest of the paths for this rel */
 	set_cheapest(rel);
 }
 
 /*
- * set_inherited_rel_pathlist
- *	  Build access paths for a inheritance tree rooted at rel
- *
- * inheritlist is a list of RT indexes of all tables in the inheritance tree,
- * including a duplicate of the parent itself.	Note we will not come here
- * unless there's at least one child in addition to the parent.
+ * set_append_rel_pathlist
+ *	  Build access paths for an "append relation"
  *
- * NOTE: the passed-in rel and RTE will henceforth represent the appended
- * result of the whole inheritance tree.  The members of inheritlist represent
- * the individual tables --- in particular, the inheritlist member that is a
- * duplicate of the parent RTE represents the parent table alone.
- * We will generate plans to scan the individual tables that refer to
- * the inheritlist RTEs, whereas Vars elsewhere in the plan tree that
- * refer to the original RTE are taken to refer to the append output.
- * In particular, this means we have separate RelOptInfos for the parent
- * table and for the append output, which is a good thing because they're
- * not the same size.
+ * The passed-in rel and RTE represent the entire append relation.	The
+ * relation's contents are computed by appending together the output of
+ * the individual member relations.  Note that in the inheritance case,
+ * the first member relation is actually the same table as is mentioned in
+ * the parent RTE ... but it has a different RTE and RelOptInfo.  This is
+ * a good thing because their outputs are not the same size.
  */
 static void
-set_inherited_rel_pathlist(Query *root, RelOptInfo *rel,
-						   Index rti, RangeTblEntry *rte,
-						   List *inheritlist)
+set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
+						Index rti, RangeTblEntry *rte)
 {
 	int			parentRTindex = rti;
-	Oid			parentOID = rte->relid;
 	List	   *subpaths = NIL;
-	List	   *il;
-
-	/*
-	 * XXX for now, can't handle inherited expansion of FOR UPDATE; can we
-	 * do better?
-	 */
-	if (intMember(parentRTindex, root->rowMarks))
-		elog(ERROR, "SELECT FOR UPDATE is not supported for inherit queries");
+	double		parent_rows;
+	double		parent_size;
+	double	   *parent_attrsizes;
+	int			nattrs;
+	ListCell   *l;
 
 	/*
-	 * The executor will check the parent table's access permissions when
-	 * it examines the parent's inheritlist entry.  There's no need to
-	 * check twice, so turn off access check bits in the original RTE.
-	 */
-	rte->checkForRead = false;
-	rte->checkForWrite = false;
-
-	/*
-	 * Initialize to compute size estimates for whole inheritance tree
+	 * Initialize to compute size estimates for whole append relation.
+	 *
+	 * We handle width estimates by weighting the widths of different child
+	 * rels proportionally to their number of rows.  This is sensible because
+	 * the use of width estimates is mainly to compute the total relation
+	 * "footprint" if we have to sort or hash it.  To do this, we sum the
+	 * total equivalent size (in "double" arithmetic) and then divide by the
+	 * total rowcount estimate.  This is done separately for the total rel
+	 * width and each attribute.
+	 *
+	 * Note: if you consider changing this logic, beware that child rels could
+	 * have zero rows and/or width, if they were excluded by constraints.
 	 */
-	rel->rows = 0;
-	rel->width = 0;
+	parent_rows = 0;
+	parent_size = 0;
+	nattrs = rel->max_attr - rel->min_attr + 1;
+	parent_attrsizes = (double *) palloc0(nattrs * sizeof(double));
 
 	/*
-	 * Generate access paths for each table in the tree (parent AND
-	 * children), and pick the cheapest path for each table.
+	 * Generate access paths for each member relation, and pick the cheapest
+	 * path for each one.
 	 */
-	foreach(il, inheritlist)
+	foreach(l, root->append_rel_list)
 	{
-		int			childRTindex = lfirsti(il);
-		RangeTblEntry *childrte;
-		Oid			childOID;
+		AppendRelInfo *appinfo = (AppendRelInfo *) lfirst(l);
+		int			childRTindex;
+		RangeTblEntry *childRTE;
 		RelOptInfo *childrel;
+		List	   *childquals;
+		Node	   *childqual;
+		Path	   *childpath;
+		ListCell   *parentvars;
+		ListCell   *childvars;
+
+		/* append_rel_list contains all append rels; ignore others */
+		if (appinfo->parent_relid != parentRTindex)
+			continue;
 
-		childrte = rt_fetch(childRTindex, root->rtable);
-		childOID = childrte->relid;
+		childRTindex = appinfo->child_relid;
+		childRTE = root->simple_rte_array[childRTindex];
 
 		/*
-		 * Make a RelOptInfo for the child so we can do planning.  Do NOT
-		 * attach the RelOptInfo to the query's base_rel_list, however,
-		 * since the child is not part of the main join tree.  Instead,
-		 * the child RelOptInfo is added to other_rel_list.
+		 * The child rel's RelOptInfo was already created during
+		 * add_base_rels_to_query.
 		 */
-		childrel = build_other_rel(root, childRTindex);
+		childrel = find_base_rel(root, childRTindex);
+		Assert(childrel->reloptkind == RELOPT_OTHER_MEMBER_REL);
 
 		/*
-		 * Copy the parent's targetlist and restriction quals to the
-		 * child, with attribute-number adjustment as needed.  We don't
-		 * bother to copy the join quals, since we can't do any joining of
-		 * the individual tables.
+		 * We have to copy the parent's targetlist and quals to the child,
+		 * with appropriate substitution of variables.	However, only the
+		 * baserestrictinfo quals are needed before we can check for
+		 * constraint exclusion; so do that first and then check to see if we
+		 * can disregard this child.
+		 *
+		 * As of 8.4, 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.  To deal with this, we strip the
+		 * RestrictInfo nodes, do the substitution, do const-simplification,
+		 * and then reconstitute the RestrictInfo layer.
 		 */
-		childrel->targetlist = (List *)
-			adjust_inherited_attrs((Node *) rel->targetlist,
-								   parentRTindex,
-								   parentOID,
-								   childRTindex,
-								   childOID);
-		childrel->baserestrictinfo = (List *)
-			adjust_inherited_attrs((Node *) rel->baserestrictinfo,
-								   parentRTindex,
-								   parentOID,
-								   childRTindex,
-								   childOID);
-		childrel->baserestrictcost = rel->baserestrictcost;
+		childquals = get_all_actual_clauses(rel->baserestrictinfo);
+		childquals = (List *) adjust_appendrel_attrs((Node *) childquals,
+													 appinfo);
+		childqual = eval_const_expressions(root, (Node *)
+										   make_ands_explicit(childquals));
+		if (childqual && IsA(childqual, Const) &&
+			(((Const *) childqual)->constisnull ||
+			 !DatumGetBool(((Const *) childqual)->constvalue)))
+		{
+			/*
+			 * Restriction reduces to constant FALSE or constant NULL after
+			 * substitution, so this child need not be scanned.
+			 */
+			set_dummy_rel_pathlist(childrel);
+			continue;
+		}
+		childquals = make_ands_implicit((Expr *) childqual);
+		childquals = make_restrictinfos_from_actual_clauses(root,
+															childquals);
+		childrel->baserestrictinfo = childquals;
+
+		if (relation_excluded_by_constraints(root, childrel, childRTE))
+		{
+			/*
+			 * This child need not be scanned, so we can omit it from the
+			 * appendrel.  Mark it with a dummy cheapest-path though, in case
+			 * best_appendrel_indexscan() looks at it later.
+			 */
+			set_dummy_rel_pathlist(childrel);
+			continue;
+		}
+
+		/* CE failed, so finish copying targetlist and join quals */
+		childrel->joininfo = (List *)
+			adjust_appendrel_attrs((Node *) rel->joininfo,
+								   appinfo);
+		childrel->reltargetlist = (List *)
+			adjust_appendrel_attrs((Node *) rel->reltargetlist,
+								   appinfo);
+
+		/*
+		 * We have to make child entries in the EquivalenceClass data
+		 * structures as well.
+		 */
+		if (rel->has_eclass_joins)
+		{
+			add_child_rel_equivalences(root, appinfo, rel, childrel);
+			childrel->has_eclass_joins = true;
+		}
+
+		/*
+		 * Note: we could compute appropriate attr_needed data for the child's
+		 * variables, by transforming the parent's attr_needed through the
+		 * translated_vars mapping.  However, currently there's no need
+		 * because attr_needed is only examined for base relations not
+		 * otherrels.  So we just leave the child's attr_needed empty.
+		 */
+
+		/*
+		 * Compute the child's access paths, and add the cheapest one to the
+		 * Append path we are constructing for the parent.
+		 *
+		 * It's possible that the child is itself an appendrel, in which case
+		 * we can "cut out the middleman" and just add its child paths to our
+		 * own list.  (We don't try to do this earlier because we need to
+		 * apply both levels of transformation to the quals.)
+		 */
+		set_rel_pathlist(root, childrel, childRTindex, childRTE);
+
+		childpath = childrel->cheapest_total_path;
+		if (IsA(childpath, AppendPath))
+			subpaths = list_concat(subpaths,
+								   ((AppendPath *) childpath)->subpaths);
+		else
+			subpaths = lappend(subpaths, childpath);
 
 		/*
-		 * Now compute child access paths, and save the cheapest.
+		 * Accumulate size information from each child.
 		 */
-		set_plain_rel_pathlist(root, childrel, childrte);
+		if (childrel->rows > 0)
+		{
+			parent_rows += childrel->rows;
+			parent_size += childrel->width * childrel->rows;
+
+			forboth(parentvars, rel->reltargetlist,
+					childvars, childrel->reltargetlist)
+			{
+				Var		   *parentvar = (Var *) lfirst(parentvars);
+				Var		   *childvar = (Var *) lfirst(childvars);
+
+				/*
+				 * Accumulate per-column estimates too.  Whole-row Vars and
+				 * PlaceHolderVars can be ignored here.
+				 */
+				if (IsA(parentvar, Var) &&
+					IsA(childvar, Var))
+				{
+					int			pndx = parentvar->varattno - rel->min_attr;
+					int			cndx = childvar->varattno - childrel->min_attr;
+
+					parent_attrsizes[pndx] += childrel->attr_widths[cndx] * childrel->rows;
+				}
+			}
+		}
+	}
 
-		subpaths = lappend(subpaths, childrel->cheapest_total_path);
+	/*
+	 * Save the finished size estimates.
+	 */
+	rel->rows = parent_rows;
+	if (parent_rows > 0)
+	{
+		int			i;
 
-		/* Also update total size estimates */
-		rel->rows += childrel->rows;
-		if (childrel->width > rel->width)
-			rel->width = childrel->width;
+		rel->width = rint(parent_size / parent_rows);
+		for (i = 0; i < nattrs; i++)
+			rel->attr_widths[i] = rint(parent_attrsizes[i] / parent_rows);
 	}
+	else
+		rel->width = 0;			/* attr_widths should be zero already */
+
+	/*
+	 * Set "raw tuples" count equal to "rows" for the appendrel; needed
+	 * because some places assume rel->tuples is valid for any baserel.
+	 */
+	rel->tuples = parent_rows;
+
+	pfree(parent_attrsizes);
 
 	/*
-	 * Finally, build Append path and install it as the only access path
-	 * for the parent rel.
+	 * Finally, build Append path and install it as the only access path for
+	 * the parent rel.	(Note: this is correct even if we have zero or one
+	 * live subpath due to constraint exclusion.)
 	 */
 	add_path(rel, (Path *) create_append_path(rel, subpaths));
 
@@ -283,68 +493,146 @@ set_inherited_rel_pathlist(Query *root, RelOptInfo *rel,
 	set_cheapest(rel);
 }
 
+/*
+ * set_dummy_rel_pathlist
+ *	  Build a dummy path for a relation that's been excluded by constraints
+ *
+ * Rather than inventing a special "dummy" path type, we represent this as an
+ * AppendPath with no members (see also IS_DUMMY_PATH macro).
+ */
+static void
+set_dummy_rel_pathlist(RelOptInfo *rel)
+{
+	/* Set dummy size estimates --- we leave attr_widths[] as zeroes */
+	rel->rows = 0;
+	rel->width = 0;
+
+	add_path(rel, (Path *) create_append_path(rel, NIL));
+
+	/* Select cheapest path (pretty easy in this case...) */
+	set_cheapest(rel);
+}
+
+/* quick-and-dirty test to see if any joining is needed */
+static bool
+has_multiple_baserels(PlannerInfo *root)
+{
+	int			num_base_rels = 0;
+	Index		rti;
+
+	for (rti = 1; rti < root->simple_rel_array_size; rti++)
+	{
+		RelOptInfo *brel = root->simple_rel_array[rti];
+
+		if (brel == NULL)
+			continue;
+
+		/* ignore RTEs that are "other rels" */
+		if (brel->reloptkind == RELOPT_BASEREL)
+			if (++num_base_rels > 1)
+				return true;
+	}
+	return false;
+}
+
 /*
  * set_subquery_pathlist
  *		Build the (single) access path for a subquery RTE
  */
 static void
-set_subquery_pathlist(Query *root, RelOptInfo *rel,
+set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					  Index rti, RangeTblEntry *rte)
 {
+	Query	   *parse = root->parse;
 	Query	   *subquery = rte->subquery;
+	bool	   *differentTypes;
+	double		tuple_fraction;
+	PlannerInfo *subroot;
+	List	   *pathkeys;
+
+	/*
+	 * Must copy the Query so that planning doesn't mess up the RTE contents
+	 * (really really need to fix the planner to not scribble on its input,
+	 * someday).
+	 */
+	subquery = copyObject(subquery);
+
+	/* We need a workspace for keeping track of set-op type coercions */
+	differentTypes = (bool *)
+		palloc0((list_length(subquery->targetList) + 1) * sizeof(bool));
 
 	/*
 	 * If there are any restriction clauses that have been attached to the
-	 * subquery relation, consider pushing them down to become HAVING
-	 * quals of the subquery itself.  (Not WHERE clauses, since they may
-	 * refer to subquery outputs that are aggregate results.  But
-	 * planner.c will transfer them into the subquery's WHERE if they do
-	 * not.)  This transformation is useful because it may allow us to
-	 * generate a better plan for the subquery than evaluating all the
-	 * subquery output rows and then filtering them.
+	 * subquery relation, consider pushing them down to become WHERE or HAVING
+	 * quals of the subquery itself.  This transformation is useful because it
+	 * may allow us to generate a better plan for the subquery than evaluating
+	 * all the subquery output rows and then filtering them.
 	 *
-	 * There are several cases where we cannot push down clauses.
-	 * Restrictions involving the subquery are checked by
-	 * subquery_is_pushdown_safe().  Also, we do not push down clauses
-	 * that contain subselects, mainly because I'm not sure it will work
-	 * correctly (the subplan hasn't yet transformed sublinks to
-	 * subselects).
+	 * There are several cases where we cannot push down clauses. Restrictions
+	 * involving the subquery are checked by subquery_is_pushdown_safe().
+	 * Restrictions on individual clauses are checked by
+	 * qual_is_pushdown_safe().  Also, we don't want to push down
+	 * pseudoconstant clauses; better to have the gating node above the
+	 * subquery.
 	 *
 	 * Non-pushed-down clauses will get evaluated as qpquals of the
 	 * SubqueryScan node.
 	 *
 	 * XXX Are there any cases where we want to make a policy decision not to
-	 * push down, because it'd result in a worse plan?
+	 * push down a pushable qual, because it'd result in a worse plan?
 	 */
 	if (rel->baserestrictinfo != NIL &&
-		subquery_is_pushdown_safe(subquery, subquery))
+		subquery_is_pushdown_safe(subquery, subquery, differentTypes))
 	{
 		/* OK to consider pushing down individual quals */
 		List	   *upperrestrictlist = NIL;
-		List	   *lst;
+		ListCell   *l;
 
-		foreach(lst, rel->baserestrictinfo)
+		foreach(l, rel->baserestrictinfo)
 		{
-			RestrictInfo *rinfo = (RestrictInfo *) lfirst(lst);
+			RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
 			Node	   *clause = (Node *) rinfo->clause;
 
-			if (contain_subplans(clause))
+			if (!rinfo->pseudoconstant &&
+				qual_is_pushdown_safe(subquery, rti, clause, differentTypes))
 			{
-				/* Keep it in the upper query */
-				upperrestrictlist = lappend(upperrestrictlist, rinfo);
+				/* Push it down */
+				subquery_push_qual(subquery, rte, rti, clause);
 			}
 			else
 			{
-				/* Push it down */
-				subquery_push_qual(subquery, rti, clause);
+				/* Keep it in the upper query */
+				upperrestrictlist = lappend(upperrestrictlist, rinfo);
 			}
 		}
 		rel->baserestrictinfo = upperrestrictlist;
 	}
 
+	pfree(differentTypes);
+
+	/*
+	 * We can safely pass the outer tuple_fraction down to the subquery if the
+	 * outer level has no joining, aggregation, or sorting to do. Otherwise
+	 * we'd better tell the subquery to plan for full retrieval. (XXX This
+	 * could probably be made more intelligent ...)
+	 */
+	if (parse->hasAggs ||
+		parse->groupClause ||
+		parse->havingQual ||
+		parse->distinctClause ||
+		parse->sortClause ||
+		has_multiple_baserels(root))
+		tuple_fraction = 0.0;	/* default case */
+	else
+		tuple_fraction = root->tuple_fraction;
+
 	/* Generate the plan for the subquery */
-	rel->subplan = subquery_planner(subquery,
-									-1.0 /* default case */ );
+	rel->subplan = subquery_planner(root->glob, subquery,
+									root,
+									false, tuple_fraction,
+									&subroot);
+	rel->subrtable = subroot->parse->rtable;
+	rel->subrowmark = subroot->parse->rowMarks;
 
 	/* Copy number of output rows from subplan */
 	rel->tuples = rel->subplan->plan_rows;
@@ -352,8 +640,11 @@ set_subquery_pathlist(Query *root, RelOptInfo *rel,
 	/* Mark rel with estimated output rows, width, etc */
 	set_baserel_size_estimates(root, rel);
 
+	/* Convert subquery pathkeys to outer representation */
+	pathkeys = convert_subquery_pathkeys(root, rel, subroot->query_pathkeys);
+
 	/* Generate appropriate path */
-	add_path(rel, create_subqueryscan_path(rel));
+	add_path(rel, create_subqueryscan_path(rel, pathkeys));
 
 	/* Select cheapest path (pretty easy in this case...) */
 	set_cheapest(rel);
@@ -364,7 +655,7 @@ set_subquery_pathlist(Query *root, RelOptInfo *rel,
  *		Build the (single) access path for a function RTE
  */
 static void
-set_function_pathlist(Query *root, RelOptInfo *rel, RangeTblEntry *rte)
+set_function_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
 {
 	/* Mark rel with estimated output rows, width, etc */
 	set_function_size_estimates(root, rel);
@@ -377,62 +668,207 @@ set_function_pathlist(Query *root, RelOptInfo *rel, RangeTblEntry *rte)
 }
 
 /*
- * make_fromexpr_rel
- *	  Build access paths for a FromExpr jointree node.
+ * set_values_pathlist
+ *		Build the (single) access path for a VALUES RTE
  */
-RelOptInfo *
-make_fromexpr_rel(Query *root, FromExpr *from)
+static void
+set_values_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
+{
+	/* Mark rel with estimated output rows, width, etc */
+	set_values_size_estimates(root, rel);
+
+	/* Generate appropriate path */
+	add_path(rel, create_valuesscan_path(root, rel));
+
+	/* Select cheapest path (pretty easy in this case...) */
+	set_cheapest(rel);
+}
+
+/*
+ * set_cte_pathlist
+ *		Build the (single) access path for a non-self-reference CTE RTE
+ */
+static void
+set_cte_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
+{
+	Plan	   *cteplan;
+	PlannerInfo *cteroot;
+	Index		levelsup;
+	int			ndx;
+	ListCell   *lc;
+	int			plan_id;
+
+	/*
+	 * Find the referenced CTE, and locate the plan previously made for it.
+	 */
+	levelsup = rte->ctelevelsup;
+	cteroot = root;
+	while (levelsup-- > 0)
+	{
+		cteroot = cteroot->parent_root;
+		if (!cteroot)			/* shouldn't happen */
+			elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
+	}
+
+	/*
+	 * Note: cte_plan_ids can be shorter than cteList, if we are still working
+	 * on planning the CTEs (ie, this is a side-reference from another CTE).
+	 * So we mustn't use forboth here.
+	 */
+	ndx = 0;
+	foreach(lc, cteroot->parse->cteList)
+	{
+		CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
+
+		if (strcmp(cte->ctename, rte->ctename) == 0)
+			break;
+		ndx++;
+	}
+	if (lc == NULL)				/* shouldn't happen */
+		elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
+	if (ndx >= list_length(cteroot->cte_plan_ids))
+		elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
+	plan_id = list_nth_int(cteroot->cte_plan_ids, ndx);
+	Assert(plan_id > 0);
+	cteplan = (Plan *) list_nth(root->glob->subplans, plan_id - 1);
+
+	/* Mark rel with estimated output rows, width, etc */
+	set_cte_size_estimates(root, rel, cteplan);
+
+	/* Generate appropriate path */
+	add_path(rel, create_ctescan_path(root, rel));
+
+	/* Select cheapest path (pretty easy in this case...) */
+	set_cheapest(rel);
+}
+
+/*
+ * set_worktable_pathlist
+ *		Build the (single) access path for a self-reference CTE RTE
+ */
+static void
+set_worktable_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
+{
+	Plan	   *cteplan;
+	PlannerInfo *cteroot;
+	Index		levelsup;
+
+	/*
+	 * We need to find the non-recursive term's plan, which is in the plan
+	 * level that's processing the recursive UNION, which is one level *below*
+	 * where the CTE comes from.
+	 */
+	levelsup = rte->ctelevelsup;
+	if (levelsup == 0)			/* shouldn't happen */
+		elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
+	levelsup--;
+	cteroot = root;
+	while (levelsup-- > 0)
+	{
+		cteroot = cteroot->parent_root;
+		if (!cteroot)			/* shouldn't happen */
+			elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
+	}
+	cteplan = cteroot->non_recursive_plan;
+	if (!cteplan)				/* shouldn't happen */
+		elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
+
+	/* Mark rel with estimated output rows, width, etc */
+	set_cte_size_estimates(root, rel, cteplan);
+
+	/* Generate appropriate path */
+	add_path(rel, create_worktablescan_path(root, rel));
+
+	/* Select cheapest path (pretty easy in this case...) */
+	set_cheapest(rel);
+}
+
+/*
+ * make_rel_from_joinlist
+ *	  Build access paths using a "joinlist" to guide the join path search.
+ *
+ * See comments for deconstruct_jointree() for definition of the joinlist
+ * data structure.
+ */
+static RelOptInfo *
+make_rel_from_joinlist(PlannerInfo *root, List *joinlist)
 {
 	int			levels_needed;
-	List	   *initial_rels = NIL;
-	List	   *jt;
+	List	   *initial_rels;
+	ListCell   *jl;
 
 	/*
-	 * Count the number of child jointree nodes.  This is the depth of the
-	 * dynamic-programming algorithm we must employ to consider all ways
-	 * of joining the child nodes.
+	 * Count the number of child joinlist nodes.  This is the depth of the
+	 * dynamic-programming algorithm we must employ to consider all ways of
+	 * joining the child nodes.
 	 */
-	levels_needed = length(from->fromlist);
+	levels_needed = list_length(joinlist);
 
 	if (levels_needed <= 0)
 		return NULL;			/* nothing to do? */
 
 	/*
-	 * Construct a list of rels corresponding to the child jointree nodes.
+	 * Construct a list of rels corresponding to the child joinlist nodes.
 	 * This may contain both base rels and rels constructed according to
-	 * explicit JOIN directives.
+	 * sub-joinlists.
 	 */
-	foreach(jt, from->fromlist)
+	initial_rels = NIL;
+	foreach(jl, joinlist)
 	{
-		Node	   *jtnode = (Node *) lfirst(jt);
+		Node	   *jlnode = (Node *) lfirst(jl);
+		RelOptInfo *thisrel;
+
+		if (IsA(jlnode, RangeTblRef))
+		{
+			int			varno = ((RangeTblRef *) jlnode)->rtindex;
+
+			thisrel = find_base_rel(root, varno);
+		}
+		else if (IsA(jlnode, List))
+		{
+			/* Recurse to handle subproblem */
+			thisrel = make_rel_from_joinlist(root, (List *) jlnode);
+		}
+		else
+		{
+			elog(ERROR, "unrecognized joinlist node type: %d",
+				 (int) nodeTag(jlnode));
+			thisrel = NULL;		/* keep compiler quiet */
+		}
 
-		initial_rels = lappend(initial_rels,
-							   make_jointree_rel(root, jtnode));
+		initial_rels = lappend(initial_rels, thisrel);
 	}
 
 	if (levels_needed == 1)
 	{
 		/*
-		 * Single jointree node, so we're done.
+		 * Single joinlist node, so we're done.
 		 */
-		return (RelOptInfo *) lfirst(initial_rels);
+		return (RelOptInfo *) linitial(initial_rels);
 	}
 	else
 	{
 		/*
 		 * Consider the different orders in which we could join the rels,
-		 * using either GEQO or regular optimizer.
+		 * using a plugin, GEQO, or the regular join search code.
+		 *
+		 * We put the initial_rels list into a PlannerInfo field because
+		 * has_legal_joinclause() needs to look at it (ugly :-().
 		 */
-		if (enable_geqo && levels_needed >= geqo_threshold)
+		root->initial_rels = initial_rels;
+
+		if (join_search_hook)
+			return (*join_search_hook) (root, levels_needed, initial_rels);
+		else if (enable_geqo && levels_needed >= geqo_threshold)
 			return geqo(root, levels_needed, initial_rels);
 		else
-			return make_one_rel_by_joins(root, levels_needed, initial_rels);
+			return standard_join_search(root, levels_needed, initial_rels);
 	}
 }
 
 /*
- * make_one_rel_by_joins
- *	  Find all possible joinpaths for a query by successively finding ways
+ * standard_join_search
+ *	  Find possible joinpaths for a query by successively finding ways
  *	  to join component relations into join relations.
  *
  * 'levels_needed' is the number of iterations needed, ie, the number of
@@ -440,23 +876,38 @@ make_fromexpr_rel(Query *root, FromExpr *from)
  *
  * 'initial_rels' is a list of RelOptInfo nodes for each independent
  *		jointree item.	These are the components to be joined together.
+ *		Note that levels_needed == list_length(initial_rels).
  *
  * Returns the final level of join relations, i.e., the relation that is
  * the result of joining all the original relations together.
+ * At least one implementation path must be provided for this relation and
+ * all required sub-relations.
+ *
+ * To support loadable plugins that modify planner behavior by changing the
+ * join searching algorithm, we provide a hook variable that lets a plugin
+ * replace or supplement this function.  Any such hook must return the same
+ * final join relation as the standard code would, but it might have a
+ * different set of implementation paths attached, and only the sub-joinrels
+ * needed for these paths need have been instantiated.
+ *
+ * Note to plugin authors: the functions invoked during standard_join_search()
+ * modify root->join_rel_list and root->join_rel_hash.	If you want to do more
+ * than one join-order search, you'll probably need to save and restore the
+ * original states of those data structures.  See geqo_eval() for an example.
  */
-static RelOptInfo *
-make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
+RelOptInfo *
+standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
 {
 	List	  **joinitems;
 	int			lev;
 	RelOptInfo *rel;
 
 	/*
-	 * We employ a simple "dynamic programming" algorithm: we first find
-	 * all ways to build joins of two jointree items, then all ways to
-	 * build joins of three items (from two-item joins and single items),
-	 * then four-item joins, and so on until we have considered all ways
-	 * to join all the items into one rel.
+	 * We employ a simple "dynamic programming" algorithm: we first find all
+	 * ways to build joins of two jointree items, then all ways to build joins
+	 * of three items (from two-item joins and single items), then four-item
+	 * joins, and so on until we have considered all ways to join all the
+	 * items into one rel.
 	 *
 	 * joinitems[j] is a list of all the j-item rels.  Initially we set
 	 * joinitems[1] to represent all the single-jointree-item relations.
@@ -467,14 +918,14 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
 
 	for (lev = 2; lev <= levels_needed; lev++)
 	{
-		List	   *x;
+		ListCell   *x;
 
 		/*
 		 * Determine all possible pairs of relations to be joined at this
 		 * level, and build paths for making each one from every available
 		 * pair of lower-level relations.
 		 */
-		joinitems[lev] = make_rels_by_joins(root, lev, joinitems);
+		joinitems[lev] = join_search_one_level(root, lev, joinitems);
 
 		/*
 		 * Do cleanup work on each just-processed rel.
@@ -483,16 +934,6 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
 		{
 			rel = (RelOptInfo *) lfirst(x);
 
-#ifdef NOT_USED
-
-			/*
-			 * * for each expensive predicate in each path in each
-			 * distinct rel, * consider doing pullup  -- JMH
-			 */
-			if (XfuncMode != XFUNC_NOPULL && XfuncMode != XFUNC_OFF)
-				xfunc_trypullup(rel);
-#endif
-
 			/* Find and save the cheapest paths for this rel */
 			set_cheapest(rel);
 
@@ -505,9 +946,11 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
 	/*
 	 * We should have a single rel at the final level.
 	 */
-	Assert(length(joinitems[levels_needed]) == 1);
+	if (joinitems[levels_needed] == NIL)
+		elog(ERROR, "failed to build any %d-way joins", levels_needed);
+	Assert(list_length(joinitems[levels_needed]) == 1);
 
-	rel = (RelOptInfo *) lfirst(joinitems[levels_needed]);
+	rel = (RelOptInfo *) linitial(joinitems[levels_needed]);
 
 	return rel;
 }
@@ -525,38 +968,35 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
  *
  * Conditions checked here:
  *
- * 1. If the subquery has a LIMIT clause or a DISTINCT ON clause, we must
- * not push down any quals, since that could change the set of rows
- * returned.  (Actually, we could push down quals into a DISTINCT ON
- * subquery if they refer only to DISTINCT-ed output columns, but
- * checking that seems more work than it's worth.  In any case, a
- * plain DISTINCT is safe to push down past.)
+ * 1. If the subquery has a LIMIT clause, we must not push down any quals,
+ * since that could change the set of rows returned.
  *
- * 2. If the subquery has any functions returning sets in its target list,
- * we do not push down any quals, since the quals
- * might refer to those tlist items, which would mean we'd introduce
- * functions-returning-sets into the subquery's WHERE/HAVING quals.
- * (It'd be sufficient to not push down quals that refer to those
- * particular tlist items, but that's much clumsier to check.)
+ * 2. If the subquery contains any window functions, we can't push quals
+ * into it, because that could change the results.
  *
  * 3. If the subquery contains EXCEPT or EXCEPT ALL set ops we cannot push
- * quals into it, because that would change the results.  For subqueries
- * using UNION/UNION ALL/INTERSECT/INTERSECT ALL, we can push the quals
- * into each component query, so long as all the component queries share
- * identical output types.	(That restriction could probably be relaxed,
- * but it would take much more code to include type coercion code into
- * the quals, and I'm also concerned about possible semantic gotchas.)
+ * quals into it, because that could change the results.
+ *
+ * 4. For subqueries using UNION/UNION ALL/INTERSECT/INTERSECT ALL, we can
+ * push quals into each component query, but the quals can only reference
+ * subquery columns that suffer no type coercions in the set operation.
+ * Otherwise there are possible semantic gotchas.  So, we check the
+ * component queries to see if any of them have different output types;
+ * differentTypes[k] is set true if column k has different type in any
+ * component.
  */
 static bool
-subquery_is_pushdown_safe(Query *subquery, Query *topquery)
+subquery_is_pushdown_safe(Query *subquery, Query *topquery,
+						  bool *differentTypes)
 {
 	SetOperationStmt *topop;
 
-	/* Check points 1 and 2 */
-	if (subquery->limitOffset != NULL ||
-		subquery->limitCount != NULL ||
-		has_distinct_on_clause(subquery) ||
-		expression_returns_set((Node *) subquery->targetList))
+	/* Check point 1 */
+	if (subquery->limitOffset != NULL || subquery->limitCount != NULL)
+		return false;
+
+	/* Check point 2 */
+	if (subquery->hasWindowFuncs)
 		return false;
 
 	/* Are we at top level, or looking at a setop component? */
@@ -564,7 +1004,8 @@ subquery_is_pushdown_safe(Query *subquery, Query *topquery)
 	{
 		/* Top level, so check any component queries */
 		if (subquery->setOperations != NULL)
-			if (!recurse_pushdown_safe(subquery->setOperations, topquery))
+			if (!recurse_pushdown_safe(subquery->setOperations, topquery,
+									   differentTypes))
 				return false;
 	}
 	else
@@ -572,14 +1013,12 @@ subquery_is_pushdown_safe(Query *subquery, Query *topquery)
 		/* Setop component must not have more components (too weird) */
 		if (subquery->setOperations != NULL)
 			return false;
-		/* Setop component output types must match top level */
+		/* Check whether setop component output types match top level */
 		topop = (SetOperationStmt *) topquery->setOperations;
 		Assert(topop && IsA(topop, SetOperationStmt));
-		if (!tlist_same_datatypes(subquery->targetList,
-								  topop->colTypes,
-								  true))
-			return false;
-
+		compare_tlist_datatypes(subquery->targetList,
+								topop->colTypes,
+								differentTypes);
 	}
 	return true;
 }
@@ -588,7 +1027,8 @@ subquery_is_pushdown_safe(Query *subquery, Query *topquery)
  * Helper routine to recurse through setOperations tree
  */
 static bool
-recurse_pushdown_safe(Node *setOp, Query *topquery)
+recurse_pushdown_safe(Node *setOp, Query *topquery,
+					  bool *differentTypes)
 {
 	if (IsA(setOp, RangeTblRef))
 	{
@@ -597,7 +1037,7 @@ recurse_pushdown_safe(Node *setOp, Query *topquery)
 		Query	   *subquery = rte->subquery;
 
 		Assert(subquery != NULL);
-		return subquery_is_pushdown_safe(subquery, topquery);
+		return subquery_is_pushdown_safe(subquery, topquery, differentTypes);
 	}
 	else if (IsA(setOp, SetOperationStmt))
 	{
@@ -607,52 +1047,232 @@ recurse_pushdown_safe(Node *setOp, Query *topquery)
 		if (op->op == SETOP_EXCEPT)
 			return false;
 		/* Else recurse */
-		if (!recurse_pushdown_safe(op->larg, topquery))
+		if (!recurse_pushdown_safe(op->larg, topquery, differentTypes))
 			return false;
-		if (!recurse_pushdown_safe(op->rarg, topquery))
+		if (!recurse_pushdown_safe(op->rarg, topquery, differentTypes))
 			return false;
 	}
 	else
 	{
-		elog(ERROR, "recurse_pushdown_safe: unexpected node %d",
+		elog(ERROR, "unrecognized node type: %d",
 			 (int) nodeTag(setOp));
 	}
 	return true;
 }
 
+/*
+ * Compare tlist's datatypes against the list of set-operation result types.
+ * For any items that are different, mark the appropriate element of
+ * differentTypes[] to show that this column will have type conversions.
+ *
+ * We don't have to care about typmods here: the only allowed difference
+ * between set-op input and output typmods is input is a specific typmod
+ * and output is -1, and that does not require a coercion.
+ */
+static void
+compare_tlist_datatypes(List *tlist, List *colTypes,
+						bool *differentTypes)
+{
+	ListCell   *l;
+	ListCell   *colType = list_head(colTypes);
+
+	foreach(l, tlist)
+	{
+		TargetEntry *tle = (TargetEntry *) lfirst(l);
+
+		if (tle->resjunk)
+			continue;			/* ignore resjunk columns */
+		if (colType == NULL)
+			elog(ERROR, "wrong number of tlist entries");
+		if (exprType((Node *) tle->expr) != lfirst_oid(colType))
+			differentTypes[tle->resno] = true;
+		colType = lnext(colType);
+	}
+	if (colType != NULL)
+		elog(ERROR, "wrong number of tlist entries");
+}
+
+/*
+ * qual_is_pushdown_safe - is a particular qual safe to push down?
+ *
+ * qual is a restriction clause applying to the given subquery (whose RTE
+ * has index rti in the parent query).
+ *
+ * Conditions checked here:
+ *
+ * 1. The qual must not contain any subselects (mainly because I'm not sure
+ * it will work correctly: sublinks will already have been transformed into
+ * subplans in the qual, but not in the subquery).
+ *
+ * 2. The qual must not refer to the whole-row output of the subquery
+ * (since there is no easy way to name that within the subquery itself).
+ *
+ * 3. The qual must not refer to any subquery output columns that were
+ * found to have inconsistent types across a set operation tree by
+ * subquery_is_pushdown_safe().
+ *
+ * 4. If the subquery uses DISTINCT ON, we must not push down any quals that
+ * refer to non-DISTINCT output columns, because that could change the set
+ * of rows returned.  (This condition is vacuous for DISTINCT, because then
+ * there are no non-DISTINCT output columns, so we needn't check.  But note
+ * we are assuming that the qual can't distinguish values that the DISTINCT
+ * operator sees as equal.	This is a bit shaky but we have no way to test
+ * for the case, and it's unlikely enough that we shouldn't refuse the
+ * optimization just because it could theoretically happen.)
+ *
+ * 5. We must not push down any quals that refer to subselect outputs that
+ * return sets, else we'd introduce functions-returning-sets into the
+ * subquery's WHERE/HAVING quals.
+ *
+ * 6. We must not push down any quals that refer to subselect outputs that
+ * contain volatile functions, for fear of introducing strange results due
+ * to multiple evaluation of a volatile function.
+ */
+static bool
+qual_is_pushdown_safe(Query *subquery, Index rti, Node *qual,
+					  bool *differentTypes)
+{
+	bool		safe = true;
+	List	   *vars;
+	ListCell   *vl;
+	Bitmapset  *tested = NULL;
+
+	/* Refuse subselects (point 1) */
+	if (contain_subplans(qual))
+		return false;
+
+	/*
+	 * It would be unsafe to push down window function calls, but at least for
+	 * the moment we could never see any in a qual anyhow.
+	 */
+	Assert(!contain_window_function(qual));
+
+	/*
+	 * Examine all Vars used in clause; since it's a restriction clause, all
+	 * such Vars must refer to subselect output columns.
+	 */
+	vars = pull_var_clause(qual, PVC_INCLUDE_PLACEHOLDERS);
+	foreach(vl, vars)
+	{
+		Var		   *var = (Var *) lfirst(vl);
+		TargetEntry *tle;
+
+		/*
+		 * XXX Punt if we find any PlaceHolderVars in the restriction clause.
+		 * It's not clear whether a PHV could safely be pushed down, and even
+		 * less clear whether such a situation could arise in any cases of
+		 * practical interest anyway.  So for the moment, just refuse to push
+		 * down.
+		 */
+		if (!IsA(var, Var))
+		{
+			safe = false;
+			break;
+		}
+
+		Assert(var->varno == rti);
+
+		/* Check point 2 */
+		if (var->varattno == 0)
+		{
+			safe = false;
+			break;
+		}
+
+		/*
+		 * We use a bitmapset to avoid testing the same attno more than once.
+		 * (NB: this only works because subquery outputs can't have negative
+		 * attnos.)
+		 */
+		if (bms_is_member(var->varattno, tested))
+			continue;
+		tested = bms_add_member(tested, var->varattno);
+
+		/* Check point 3 */
+		if (differentTypes[var->varattno])
+		{
+			safe = false;
+			break;
+		}
+
+		/* Must find the tlist element referenced by the Var */
+		tle = get_tle_by_resno(subquery->targetList, var->varattno);
+		Assert(tle != NULL);
+		Assert(!tle->resjunk);
+
+		/* If subquery uses DISTINCT ON, check point 4 */
+		if (subquery->hasDistinctOn &&
+			!targetIsInSortList(tle, InvalidOid, subquery->distinctClause))
+		{
+			/* non-DISTINCT column, so fail */
+			safe = false;
+			break;
+		}
+
+		/* Refuse functions returning sets (point 5) */
+		if (expression_returns_set((Node *) tle->expr))
+		{
+			safe = false;
+			break;
+		}
+
+		/* Refuse volatile functions (point 6) */
+		if (contain_volatile_functions((Node *) tle->expr))
+		{
+			safe = false;
+			break;
+		}
+	}
+
+	list_free(vars);
+	bms_free(tested);
+
+	return safe;
+}
+
 /*
  * subquery_push_qual - push down a qual that we have determined is safe
  */
 static void
-subquery_push_qual(Query *subquery, Index rti, Node *qual)
+subquery_push_qual(Query *subquery, RangeTblEntry *rte, Index rti, Node *qual)
 {
 	if (subquery->setOperations != NULL)
 	{
 		/* Recurse to push it separately to each component query */
-		recurse_push_qual(subquery->setOperations, subquery, rti, qual);
+		recurse_push_qual(subquery->setOperations, subquery,
+						  rte, rti, qual);
 	}
 	else
 	{
 		/*
-		 * We need to replace Vars in the qual (which must refer to
-		 * outputs of the subquery) with copies of the subquery's
-		 * targetlist expressions.	Note that at this point, any uplevel
-		 * Vars in the qual should have been replaced with Params, so they
-		 * need no work.
+		 * We need to replace Vars in the qual (which must refer to outputs of
+		 * the subquery) with copies of the subquery's targetlist expressions.
+		 * Note that at this point, any uplevel Vars in the qual should have
+		 * been replaced with Params, so they need no work.
 		 *
 		 * This step also ensures that when we are pushing into a setop tree,
 		 * each component query gets its own copy of the qual.
 		 */
-		qual = ResolveNew(qual, rti, 0,
+		qual = ResolveNew(qual, rti, 0, rte,
 						  subquery->targetList,
-						  CMD_SELECT, 0);
-		subquery->havingQual = make_and_qual(subquery->havingQual,
-											 qual);
+						  CMD_SELECT, 0,
+						  &subquery->hasSubLinks);
+
+		/*
+		 * Now attach the qual to the proper place: normally WHERE, but if the
+		 * subquery uses grouping or aggregation, put it in HAVING (since the
+		 * qual really refers to the group-result rows).
+		 */
+		if (subquery->hasAggs || subquery->groupClause || subquery->havingQual)
+			subquery->havingQual = make_and_qual(subquery->havingQual, qual);
+		else
+			subquery->jointree->quals =
+				make_and_qual(subquery->jointree->quals, qual);
 
 		/*
 		 * We need not change the subquery's hasAggs or hasSublinks flags,
-		 * since we can't be pushing down any aggregates that weren't
-		 * there before, and we don't push down subselects at all.
+		 * since we can't be pushing down any aggregates that weren't there
+		 * before, and we don't push down subselects at all.
 		 */
 	}
 }
@@ -662,27 +1282,27 @@ subquery_push_qual(Query *subquery, Index rti, Node *qual)
  */
 static void
 recurse_push_qual(Node *setOp, Query *topquery,
-				  Index rti, Node *qual)
+				  RangeTblEntry *rte, Index rti, Node *qual)
 {
 	if (IsA(setOp, RangeTblRef))
 	{
 		RangeTblRef *rtr = (RangeTblRef *) setOp;
-		RangeTblEntry *rte = rt_fetch(rtr->rtindex, topquery->rtable);
-		Query	   *subquery = rte->subquery;
+		RangeTblEntry *subrte = rt_fetch(rtr->rtindex, topquery->rtable);
+		Query	   *subquery = subrte->subquery;
 
 		Assert(subquery != NULL);
-		subquery_push_qual(subquery, rti, qual);
+		subquery_push_qual(subquery, rte, rti, qual);
 	}
 	else if (IsA(setOp, SetOperationStmt))
 	{
 		SetOperationStmt *op = (SetOperationStmt *) setOp;
 
-		recurse_push_qual(op->larg, topquery, rti, qual);
-		recurse_push_qual(op->rarg, topquery, rti, qual);
+		recurse_push_qual(op->larg, topquery, rte, rti, qual);
+		recurse_push_qual(op->rarg, topquery, rte, rti, qual);
 	}
 	else
 	{
-		elog(ERROR, "recurse_push_qual: unexpected node %d",
+		elog(ERROR, "unrecognized node type: %d",
 			 (int) nodeTag(setOp));
 	}
 }
@@ -696,33 +1316,38 @@ recurse_push_qual(Node *setOp, Query *topquery,
 static void
 print_relids(Relids relids)
 {
-	List	   *l;
+	Relids		tmprelids;
+	int			x;
+	bool		first = true;
 
-	foreach(l, relids)
+	tmprelids = bms_copy(relids);
+	while ((x = bms_first_member(tmprelids)) >= 0)
 	{
-		printf("%d", lfirsti(l));
-		if (lnext(l))
+		if (!first)
 			printf(" ");
+		printf("%d", x);
+		first = false;
 	}
+	bms_free(tmprelids);
 }
 
 static void
-print_restrictclauses(Query *root, List *clauses)
+print_restrictclauses(PlannerInfo *root, List *clauses)
 {
-	List	   *l;
+	ListCell   *l;
 
 	foreach(l, clauses)
 	{
 		RestrictInfo *c = lfirst(l);
 
-		print_expr((Node *) c->clause, root->rtable);
+		print_expr((Node *) c->clause, root->parse->rtable);
 		if (lnext(l))
 			printf(", ");
 	}
 }
 
 static void
-print_path(Query *root, Path *path, int indent)
+print_path(PlannerInfo *root, Path *path, int indent)
 {
 	const char *ptype;
 	bool		join = false;
@@ -737,6 +1362,15 @@ print_path(Query *root, Path *path, int indent)
 		case T_IndexPath:
 			ptype = "IdxScan";
 			break;
+		case T_BitmapHeapPath:
+			ptype = "BitmapHeapScan";
+			break;
+		case T_BitmapAndPath:
+			ptype = "BitmapAndPath";
+			break;
+		case T_BitmapOrPath:
+			ptype = "BitmapOrPath";
+			break;
 		case T_TidPath:
 			ptype = "TidScan";
 			break;
@@ -745,7 +1379,6 @@ print_path(Query *root, Path *path, int indent)
 			break;
 		case T_ResultPath:
 			ptype = "Result";
-			subpath = ((ResultPath *) path)->subpath;
 			break;
 		case T_MaterialPath:
 			ptype = "Material";
@@ -755,6 +1388,10 @@ print_path(Query *root, Path *path, int indent)
 			ptype = "Unique";
 			subpath = ((UniquePath *) path)->subpath;
 			break;
+		case T_NoOpPath:
+			ptype = "NoOp";
+			subpath = ((NoOpPath *) path)->subpath;
+			break;
 		case T_NestPath:
 			ptype = "NestLoop";
 			join = true;
@@ -789,7 +1426,7 @@ print_path(Query *root, Path *path, int indent)
 		for (i = 0; i < indent; i++)
 			printf("\t");
 		printf("  pathkeys: ");
-		print_pathkeys(path->pathkeys, root->rtable);
+		print_pathkeys(path->pathkeys, root->parse->rtable);
 	}
 
 	if (join)
@@ -825,9 +1462,9 @@ print_path(Query *root, Path *path, int indent)
 }
 
 void
-debug_print_rel(Query *root, RelOptInfo *rel)
+debug_print_rel(PlannerInfo *root, RelOptInfo *rel)
 {
-	List	   *l;
+	ListCell   *l;
 
 	printf("RELOPTINFO (");
 	print_relids(rel->relids);
@@ -840,14 +1477,10 @@ debug_print_rel(Query *root, RelOptInfo *rel)
 		printf("\n");
 	}
 
-	foreach(l, rel->joininfo)
+	if (rel->joininfo)
 	{
-		JoinInfo   *j = (JoinInfo *) lfirst(l);
-
-		printf("\tjoininfo (");
-		print_relids(j->unjoined_relids);
-		printf("): ");
-		print_restrictclauses(root, j->jinfo_restrictinfo);
+		printf("\tjoininfo: ");
+		print_restrictclauses(root, rel->joininfo);
 		printf("\n");
 	}