First cut at planner support for bitmap index scans. Lots to do yet,

but the code is basically working.  Along the way, rewrite the entire
approach to processing OR index conditions, and make it work in join
cases for the first time ever.  orindxpath.c is now basically obsolete,
but I left it in for the time being to allow easy comparison testing
against the old implementation.

Author: tglsfdc

src/backend/commands/explain.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994-5, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.133 2005/04/19 22:35:10 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.134 2005/04/22 21:58:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -847,9 +847,14 @@ explain_outNode(StringInfo str,
 		for (i = 0; i < indent; i++)
 			appendStringInfo(str, "  ");
 		appendStringInfo(str, "  ->  ");
+		/*
+		 * Ordinarily we don't pass down our own outer_plan value to our
+		 * child nodes, but in bitmap scan trees we must, since the bottom
+		 * BitmapIndexScan nodes may have outer references.
+		 */
 		explain_outNode(str, outerPlan(plan),
 						outerPlanState(planstate),
-						NULL,
+						IsA(plan, BitmapHeapScan) ? outer_plan : NULL,
 						indent + 3, es);
 	}
 
@@ -907,7 +912,7 @@ explain_outNode(StringInfo str,
 
 			explain_outNode(str, subnode,
 							bitmapandstate->bitmapplans[j],
-							NULL,
+							outer_plan,	/* pass down same outer plan */
 							indent + 3, es);
 			j++;
 		}
@@ -931,7 +936,7 @@ explain_outNode(StringInfo str,
 
 			explain_outNode(str, subnode,
 							bitmaporstate->bitmapplans[j],
-							NULL,
+							outer_plan,	/* pass down same outer plan */
 							indent + 3, es);
 			j++;
 		}

src/backend/executor/nodeBitmapIndexscan.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.2 2005/04/20 15:48:36 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.3 2005/04/22 21:58:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -492,7 +492,8 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate)
 		indexstate->biss_RuntimeKeyInfo = NULL;
 		indexstate->biss_RuntimeContext = NULL;
 		/* Get rid of the speculatively-allocated flag array, too */
-		pfree(runtimeKeyInfo);
+		if (runtimeKeyInfo)
+			pfree(runtimeKeyInfo);
 	}
 
 	/*

src/backend/optimizer/path/costsize.c

@@ -49,7 +49,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.144 2005/04/21 19:18:12 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.145 2005/04/22 21:58:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -104,7 +104,6 @@ bool		enable_hashjoin = true;
 
 
 static bool cost_qual_eval_walker(Node *node, QualCost *total);
-static void cost_bitmap_tree_node(Path *path, Cost *cost, Selectivity *selec);
 static Selectivity approx_selectivity(Query *root, List *quals,
 				   JoinType jointype);
 static Selectivity join_in_selectivity(JoinPath *path, Query *root);
@@ -474,8 +473,11 @@ cost_bitmap_heap_scan(Path *path, Query *root, RelOptInfo *baserel,
 	 * For lack of a better idea, interpolate like this to determine the
 	 * cost per page.
 	 */
-	cost_per_page = random_page_cost -
-		(random_page_cost - 1.0) * sqrt(pages_fetched / T);
+	if (pages_fetched >= 2.0)
+		cost_per_page = random_page_cost -
+			(random_page_cost - 1.0) * sqrt(pages_fetched / T);
+	else
+		cost_per_page = random_page_cost;
 
 	run_cost += pages_fetched * cost_per_page;
 
@@ -500,7 +502,7 @@ cost_bitmap_heap_scan(Path *path, Query *root, RelOptInfo *baserel,
  * cost_bitmap_tree_node
  *		Extract cost and selectivity from a bitmap tree node (index/and/or)
  */
-static void
+void
 cost_bitmap_tree_node(Path *path, Cost *cost, Selectivity *selec)
 {
 	if (IsA(path, IndexPath))