Experiment with using EXPLAIN COSTS OFF in regression tests.

This is a simple test to see whether COSTS OFF will help much with getting
EXPLAIN output that's sufficiently platform-independent for use in the
regression tests.  The planner does have some freedom of choice in these
examples (plain via bitmap indexscan), so I'm not sure what will happen.

src/test/regress/expected/create_index.out

@@ -113,9 +113,20 @@ SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
 SET enable_seqscan = OFF;
 SET enable_indexscan = ON;
 SET enable_bitmapscan = ON;
--- there's no easy way to check that these commands actually use
--- the index, unfortunately.  (EXPLAIN would work, but its output
--- changes too often for me to want to put an EXPLAIN in the test...)
+EXPLAIN (COSTS OFF)
+SELECT * FROM fast_emp4000
+    WHERE home_base @ '(200,200),(2000,1000)'::box
+    ORDER BY (home_base[0])[0];
+                              QUERY PLAN                              
+----------------------------------------------------------------------
+ Sort
+   Sort Key: ((home_base[0])[0])
+   ->  Bitmap Heap Scan on fast_emp4000
+         Recheck Cond: (home_base @ '(2000,1000),(200,200)'::box)
+         ->  Bitmap Index Scan on grect2ind
+               Index Cond: (home_base @ '(2000,1000),(200,200)'::box)
+(6 rows)
+
 SELECT * FROM fast_emp4000
     WHERE home_base @ '(200,200),(2000,1000)'::box
     ORDER BY (home_base[0])[0];
@@ -125,18 +136,51 @@ SELECT * FROM fast_emp4000
  (1444,403),(1346,344)
 (2 rows)
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
+                            QUERY PLAN                             
+-------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on fast_emp4000
+         Recheck Cond: (home_base && '(1000,1000),(0,0)'::box)
+         ->  Bitmap Index Scan on grect2ind
+               Index Cond: (home_base && '(1000,1000),(0,0)'::box)
+(5 rows)
+
 SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
  count 
 -------
      2
 (1 row)
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
+                  QUERY PLAN                   
+-----------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on fast_emp4000
+         Recheck Cond: (home_base IS NULL)
+         ->  Bitmap Index Scan on grect2ind
+               Index Cond: (home_base IS NULL)
+(5 rows)
+
 SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
  count 
 -------
    278
 (1 row)
 
+EXPLAIN (COSTS OFF)
+SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
+    ORDER BY (poly_center(f1))[0];
+                        QUERY PLAN                         
+-----------------------------------------------------------
+ Sort
+   Sort Key: ((poly_center(f1))[0])
+   ->  Index Scan using gpolygonind on polygon_tbl
+         Index Cond: (f1 ~ '((1,1),(2,2),(2,1))'::polygon)
+(4 rows)
+
 SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
     ORDER BY (poly_center(f1))[0];
          f1          
@@ -144,6 +188,17 @@ SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
  ((2,0),(2,4),(0,0))
 (1 row)
 
+EXPLAIN (COSTS OFF)
+SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
+    ORDER BY area(f1);
+                    QUERY PLAN                    
+--------------------------------------------------
+ Sort
+   Sort Key: (area(f1))
+   ->  Index Scan using gcircleind on circle_tbl
+         Index Cond: (f1 && '<(1,-2),1>'::circle)
+(4 rows)
+
 SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
     ORDER BY area(f1);
       f1       
@@ -154,12 +209,34 @@ SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
  <(100,1),115>
 (4 rows)
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
+                            QUERY PLAN                            
+------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on gpolygon_tbl
+         Recheck Cond: (f1 && '((1000,1000),(0,0))'::polygon)
+         ->  Bitmap Index Scan on ggpolygonind
+               Index Cond: (f1 && '((1000,1000),(0,0))'::polygon)
+(5 rows)
+
 SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
  count 
 -------
      2
 (1 row)
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
+                         QUERY PLAN                          
+-------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on gcircle_tbl
+         Recheck Cond: (f1 && '<(500,500),500>'::circle)
+         ->  Bitmap Index Scan on ggcircleind
+               Index Cond: (f1 && '<(500,500),500>'::circle)
+(5 rows)
+
 SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
  count 
 -------

src/test/regress/sql/create_index.sql

@@ -112,25 +112,40 @@ SET enable_seqscan = OFF;
 SET enable_indexscan = ON;
 SET enable_bitmapscan = ON;
 
--- there's no easy way to check that these commands actually use
--- the index, unfortunately.  (EXPLAIN would work, but its output
--- changes too often for me to want to put an EXPLAIN in the test...)
+EXPLAIN (COSTS OFF)
+SELECT * FROM fast_emp4000
+    WHERE home_base @ '(200,200),(2000,1000)'::box
+    ORDER BY (home_base[0])[0];
 SELECT * FROM fast_emp4000
     WHERE home_base @ '(200,200),(2000,1000)'::box
     ORDER BY (home_base[0])[0];
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
 SELECT count(*) FROM fast_emp4000 WHERE home_base && '(1000,1000,0,0)'::box;
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
 SELECT count(*) FROM fast_emp4000 WHERE home_base IS NULL;
 
+EXPLAIN (COSTS OFF)
+SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
+    ORDER BY (poly_center(f1))[0];
 SELECT * FROM polygon_tbl WHERE f1 ~ '((1,1),(2,2),(2,1))'::polygon
     ORDER BY (poly_center(f1))[0];
 
+EXPLAIN (COSTS OFF)
+SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
+    ORDER BY area(f1);
 SELECT * FROM circle_tbl WHERE f1 && circle(point(1,-2), 1)
     ORDER BY area(f1);
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
 SELECT count(*) FROM gpolygon_tbl WHERE f1 && '(1000,1000,0,0)'::polygon;
 
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
 SELECT count(*) FROM gcircle_tbl WHERE f1 && '<(500,500),500>'::circle;
 
 RESET enable_seqscan;