RESET SESSION, plus related new DDL commands. Patch from Marko Kreen,

reviewed by Neil Conway. This patch adds the following DDL command
variants: RESET SESSION, RESET TEMP, RESET PLANS, CLOSE ALL, and
DEALLOCATE ALL. RESET SESSION is intended for use by connection
pool software and the like, in order to reset a client session
to something close to its initial state.

Note that while most of these command variants can be executed
inside a transaction block (but are not transaction-aware!),
RESET SESSION cannot. While this is inconsistent, it is intended
to catch programmer mistakes: RESET SESSION in an open transaction
block is probably unintended.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/test/regress/expected/portals.out b/src/test/regress/expected/portals.out
index ab62ac2705..9b22aa4dc7 100644
--- a/src/test/regress/expected/portals.out
+++ b/src/test/regress/expected/portals.out
@@ -869,3 +869,33 @@ EXECUTE cprep;
  c2   | declare c2 cursor with hold for select count_tt1_v(), count_tt1_s(); | t           | f         | f
 (1 row)
 
+-- test CLOSE ALL;
+SELECT name FROM pg_cursors ORDER BY 1;
+ name 
+------
+ c2
+(1 row)
+
+CLOSE ALL;
+SELECT name FROM pg_cursors ORDER BY 1;
+ name 
+------
+(0 rows)
+
+BEGIN;
+DECLARE foo1 CURSOR WITH HOLD FOR SELECT 1;
+DECLARE foo2 CURSOR WITHOUT HOLD FOR SELECT 1;
+SELECT name FROM pg_cursors ORDER BY 1;
+ name 
+------
+ foo1
+ foo2
+(2 rows)
+
+CLOSE ALL;
+SELECT name FROM pg_cursors ORDER BY 1;
+ name 
+------
+(0 rows)
+
+COMMIT;