check rel->baserestrictinfo for params, move support functions to utils.c

Author: funbringer

Makefile

@@ -1,7 +1,7 @@
 # contrib/pg_pathman/Makefile
 
 MODULE_big = pg_pathman
-OBJS = init.o runtimeappend.o runtime_merge_append.o pg_pathman.o dsm_array.o \
+OBJS = init.o utils.o runtimeappend.o runtime_merge_append.o pg_pathman.o dsm_array.o \
 	rangeset.o pl_funcs.o worker.o hooks.o nodes_common.o $(WIN32RES)
 
 EXTENSION = pg_pathman

hooks.c

@@ -15,11 +15,9 @@
 #include "pathman.h"
 #include "runtimeappend.h"
 #include "runtime_merge_append.h"
+#include "utils.h"
 
 
-static int cmp_tlist_vars(const void *a, const void *b);
-static List * sort_rel_tlist(List *tlist);
-
 set_join_pathlist_hook_type		set_join_pathlist_next = NULL;
 set_rel_pathlist_hook_type		set_rel_pathlist_hook_next = NULL;
 
@@ -279,6 +277,10 @@ pathman_rel_pathlist_hook(PlannerInfo *root, RelOptInfo *rel, Index rti, RangeTb
 			  pg_pathman_enable_runtime_merge_append))
 			return;
 
+		/* RuntimeAppend is pointless if there are no params in clauses */
+		if (!clause_contains_params((Node *) get_actual_clauses(rel->baserestrictinfo)))
+			return;
+
 		foreach (lc, rel->pathlist)
 		{
 			AppendPath	   *cur_path = (AppendPath *) lfirst(lc);
@@ -324,50 +326,3 @@ void pg_pathman_enable_assign_hook(bool newval, void *extra)
 		 newval ? "enabled" : "disabled");
 }
 
-/*
- * Sorts reltargetlist by Var's varattno (physical order) since
- * we can't use static build_path_tlist() for our custom nodes.
- *
- * See create_scan_plan & use_physical_tlist for more details.
- */
-static List *
-sort_rel_tlist(List *tlist)
-{
-	int			i;
-	int			plain_tlist_size = list_length(tlist);
-	Var		  **plain_tlist = palloc(plain_tlist_size * sizeof(Var *));
-	ListCell   *tlist_cell;
-	List	   *result = NIL;
-
-	i = 0;
-	foreach (tlist_cell, tlist)
-		plain_tlist[i++] = lfirst(tlist_cell);
-
-	qsort(plain_tlist, plain_tlist_size, sizeof(Var *), cmp_tlist_vars);
-
-	for (i = 0; i < plain_tlist_size; i++)
-		result = lappend(result, plain_tlist[i]);
-
-	return result;
-}
-
-/* Compare Vars by varattno */
-static int
-cmp_tlist_vars(const void *a, const void *b)
-{
-	Var *v1 = *(Var **) a;
-	Var *v2 = *(Var **) b;
-
-	Assert(IsA(v1, Var) && IsA(v2, Var));
-
-	if (v1->varattno > v2->varattno)
-		return 1;
-	else if (v1->varattno < v2->varattno)
-		return -1;
-	else
-	{
-		/* XXX: I really doubt this case is ok */
-		Assert(v1->varattno != v2->varattno);
-		return 0;
-	}
-}

nodes_common.c

@@ -230,7 +230,6 @@ create_append_path_common(PlannerInfo *root,
 	result->cpath.flags = 0;
 	result->cpath.methods = path_methods;
 
-	/* TODO: real costs */
 	result->cpath.path.startup_cost = 0.0;
 	result->cpath.path.total_cost = 0.0;
 

utils.c

@@ -0,0 +1,112 @@
+/* ------------------------------------------------------------------------
+ *
+ * utils.c
+ *		definitions of various support functions
+ *
+ * Copyright (c) 2016, Postgres Professional
+ *
+ * ------------------------------------------------------------------------
+ */
+#include "utils.h"
+#include "nodes/nodeFuncs.h"
+#include "parser/parse_param.h"
+#include "utils/builtins.h"
+#include "rewrite/rewriteManip.h"
+
+
+static bool clause_contains_params_walker(Node *node, void *context);
+
+bool
+clause_contains_params(Node *clause)
+{
+	return expression_tree_walker(clause,
+								  clause_contains_params_walker,
+								  NULL);
+}
+
+static bool
+clause_contains_params_walker(Node *node, void *context)
+{
+	if (node == NULL)
+		return false;
+	if (IsA(node, Param))
+		return true;
+	return expression_tree_walker(node,
+								  clause_contains_params_walker,
+								  context);
+}
+
+static Node *
+replace_child_var(Var *var, replace_rte_variables_context *context)
+{
+	ReplaceVarsContext *cxt = (ReplaceVarsContext *) context->callback_arg;
+	Var				   *new_var;
+
+	new_var = makeNode(Var);
+	memcpy(new_var, var, sizeof(Var));
+
+	/*
+	 * Replace a partition's Var with a Var
+	 * pointing to the RuntimeAppend's results
+	 */
+	new_var->varno = cxt->parent->relid;
+	new_var->location = -1;
+	new_var->varnoold = 0;
+
+	return (Node *) new_var;
+}
+
+Node *
+replace_child_vars_with_parent_var(Node *node, ReplaceVarsContext *context)
+{
+	return replace_rte_variables(node, context->child->relid, context->sublevels_up,
+								 replace_child_var, (void *) context, NULL);
+}
+
+/*
+ * Sorts reltargetlist by Var's varattno (physical order) since
+ * we can't use static build_path_tlist() for our custom nodes.
+ *
+ * See create_scan_plan & use_physical_tlist for more details.
+ */
+List *
+sort_rel_tlist(List *tlist)
+{
+	int			i;
+	int			plain_tlist_size = list_length(tlist);
+	Var		  **plain_tlist = palloc(plain_tlist_size * sizeof(Var *));
+	ListCell   *tlist_cell;
+	List	   *result = NIL;
+
+	i = 0;
+	foreach (tlist_cell, tlist)
+		plain_tlist[i++] = lfirst(tlist_cell);
+
+	qsort(plain_tlist, plain_tlist_size, sizeof(Var *), cmp_tlist_vars);
+
+	for (i = 0; i < plain_tlist_size; i++)
+		result = lappend(result, plain_tlist[i]);
+
+	return result;
+}
+
+/* Compare Vars by varattno */
+int
+cmp_tlist_vars(const void *a, const void *b)
+{
+	Var *v1 = *(Var **) a;
+	Var *v2 = *(Var **) b;
+
+	Assert(IsA(v1, Var) && IsA(v2, Var));
+
+	if (v1->varattno > v2->varattno)
+		return 1;
+	else if (v1->varattno < v2->varattno)
+		return -1;
+	else
+	{
+		/* XXX: I really doubt this case is ok */
+		Assert(v1->varattno != v2->varattno);
+		return 0;
+	}
+}

utils.h

@@ -0,0 +1,32 @@
+/* ------------------------------------------------------------------------
+ *
+ * utils.h
+ *		prototypes of various support functions
+ *
+ * Copyright (c) 2016, Postgres Professional
+ *
+ * ------------------------------------------------------------------------
+ */
+#ifndef UTILS_H
+#define UTILS_H
+
+#include "postgres.h"
+#include "nodes/relation.h"
+#include "nodes/nodeFuncs.h"
+
+typedef struct
+{
+	RelOptInfo *child;
+	RelOptInfo *parent;
+	int			sublevels_up;
+} ReplaceVarsContext;
+
+bool clause_contains_params(Node *clause);
+
+Node * replace_child_vars_with_parent_var(Node *node,
+										  ReplaceVarsContext *context);
+
+int cmp_tlist_vars(const void *a, const void *b);
+List * sort_rel_tlist(List *tlist);
+
+#endif