Add support for multi-row VALUES clauses as part of INSERT statements

(e.g. "INSERT ... VALUES (...), (...), ...") and elsewhere as allowed
by the spec. (e.g. similar to a FROM clause subselect). initdb required.
Joe Conway and Tom Lane.

2 files changed, 87 insertions, 2 deletions

diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 05fe268a318..1d7e20c1e8b 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.149 2006/07/14 14:52:20 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.150 2006/08/02 01:59:45 joe Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -48,6 +48,8 @@ static void set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					  Index rti, RangeTblEntry *rte);
 static void set_function_pathlist(PlannerInfo *root, RelOptInfo *rel,
 					  RangeTblEntry *rte);
+static void set_values_pathlist(PlannerInfo *root, RelOptInfo *rel,
+					  RangeTblEntry *rte);
 static RelOptInfo *make_rel_from_joinlist(PlannerInfo *root, List *joinlist);
 static RelOptInfo *make_one_rel_by_joins(PlannerInfo *root, int levels_needed,
 					  List *initial_rels);
@@ -170,6 +172,11 @@ set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, Index rti)
 		/* RangeFunction --- generate a separate plan for it */
 		set_function_pathlist(root, rel, rte);
 	}
+	else if (rel->rtekind == RTE_VALUES)
+	{
+		/* Values list --- generate a separate plan for it */
+		set_values_pathlist(root, rel, rte);
+	}
 	else
 	{
 		/* Plain relation */
@@ -538,6 +545,23 @@ set_function_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
 }
 
 /*
+ * set_values_pathlist
+ *		Build the (single) access path for a VALUES RTE
+ */
+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);
+}
+
+/*
  * make_rel_from_joinlist
  *	  Build access paths using a "joinlist" to guide the join path search.
  *
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 5f5e9ec3721..fffa25dd844 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -54,7 +54,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.164 2006/07/26 11:35:56 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.165 2006/08/02 01:59:45 joe Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -775,6 +775,36 @@ cost_functionscan(Path *path, PlannerInfo *root, RelOptInfo *baserel)
 }
 
 /*
+ * cost_valuesscan
+ *	  Determines and returns the cost of scanning a VALUES RTE.
+ */
+void
+cost_valuesscan(Path *path, PlannerInfo *root, RelOptInfo *baserel)
+{
+	Cost		startup_cost = 0;
+	Cost		run_cost = 0;
+	Cost		cpu_per_tuple;
+
+	/* Should only be applied to base relations that are values lists */
+	Assert(baserel->relid > 0);
+	Assert(baserel->rtekind == RTE_VALUES);
+
+	/*
+	 * For now, estimate list evaluation cost at one operator eval per
+	 * list (probably pretty bogus, but is it worth being smarter?)
+	 */
+	cpu_per_tuple = cpu_operator_cost;
+
+	/* Add scanning CPU costs */
+	startup_cost += baserel->baserestrictcost.startup;
+	cpu_per_tuple += cpu_tuple_cost + baserel->baserestrictcost.per_tuple;
+	run_cost += cpu_per_tuple * baserel->tuples;
+
+	path->startup_cost = startup_cost;
+	path->total_cost = startup_cost + run_cost;
+}
+
+/*
  * cost_sort
  *	  Determines and returns the cost of sorting a relation, including
  *	  the cost of reading the input data.
@@ -2023,6 +2053,37 @@ set_function_size_estimates(PlannerInfo *root, RelOptInfo *rel)
 	set_baserel_size_estimates(root, rel);
 }
 
+/*
+ * set_values_size_estimates
+ *		Set the size estimates for a base relation that is a values list.
+ *
+ * The rel's targetlist and restrictinfo list must have been constructed
+ * already.
+ *
+ * We set the same fields as set_baserel_size_estimates.
+ */
+void
+set_values_size_estimates(PlannerInfo *root, RelOptInfo *rel)
+{
+	RangeTblEntry *rte;
+
+	/* Should only be applied to base relations that are values lists */
+	Assert(rel->relid > 0);
+	rte = rt_fetch(rel->relid, root->parse->rtable);
+	Assert(rte->rtekind == RTE_VALUES);
+
+	/*
+	 * Estimate number of rows the values list will return.
+	 * We know this precisely based on the list length (well,
+	 * barring set-returning functions in list items, but that's
+	 * a refinement not catered for anywhere else either).
+	 */
+	rel->tuples = list_length(rte->values_lists);
+
+	/* Now estimate number of output rows, etc */
+	set_baserel_size_estimates(root, rel);
+}
+
 
 /*
  * set_rel_width