Add COSTS off to two EXPLAIN using tests.

Discussion: https://postgr.es/m/20180312222023.i4sgkbl4oqtstus3@alap3.anarazel.de

src/test/regress/expected/subselect.out

@@ -232,23 +232,23 @@ SELECT *, pg_typeof(f1) FROM
 (3 rows)
 
 -- ... unless there's context to suggest differently
-explain verbose select '42' union all select '43';
+explain (verbose, costs off) select '42' union all select '43';
-                   QUERY PLAN                    
+         QUERY PLAN         
--------------------------------------------------
+----------------------------
- Append  (cost=0.00..0.05 rows=2 width=32)
+ Append
-   ->  Result  (cost=0.00..0.01 rows=1 width=32)
+   ->  Result
          Output: '42'::text
-   ->  Result  (cost=0.00..0.01 rows=1 width=32)
+   ->  Result
          Output: '43'::text
 (5 rows)
 
-explain verbose select '42' union all select 43;
+explain (verbose, costs off) select '42' union all select 43;
-                   QUERY PLAN                   
+     QUERY PLAN     
-------------------------------------------------
+--------------------
- Append  (cost=0.00..0.05 rows=2 width=4)
+ Append
-   ->  Result  (cost=0.00..0.01 rows=1 width=4)
+   ->  Result
          Output: 42
-   ->  Result  (cost=0.00..0.01 rows=1 width=4)
+   ->  Result
          Output: 43
 (5 rows)
 

src/test/regress/sql/subselect.sql

@@ -99,8 +99,8 @@ SELECT *, pg_typeof(f1) FROM
 
 -- ... unless there's context to suggest differently
 
-explain verbose select '42' union all select '43';
+explain (verbose, costs off) select '42' union all select '43';
-explain verbose select '42' union all select 43;
+explain (verbose, costs off) select '42' union all select 43;
 
 -- check materialization of an initplan reference (bug #14524)
 explain (verbose, costs off)