Invent ResourceOwner mechanism as per my recent proposal, and use it to

keep track of portal-related resources separately from transaction-related
resources.  This allows cursors to work in a somewhat sane fashion with
nested transactions.  For now, cursor behavior is non-subtransactional,
that is a cursor's state does not roll back if you abort a subtransaction
that fetched from the cursor.  We might want to change that later.

2 files changed, 88 insertions, 0 deletions

diff --git a/src/test/regress/expected/transactions.out b/src/test/regress/expected/transactions.out
index c2fdc231039..cc3004dbb28 100644
--- a/src/test/regress/expected/transactions.out
+++ b/src/test/regress/expected/transactions.out
@@ -191,6 +191,72 @@ SELECT 1;			-- this should work
         1
 (1 row)
 
+-- check non-transactional behavior of cursors
+BEGIN;
+	DECLARE c CURSOR FOR SELECT unique2 FROM tenk1;
+	BEGIN;
+		FETCH 10 FROM c;
+ unique2 
+---------
+       0
+       1
+       2
+       3
+       4
+       5
+       6
+       7
+       8
+       9
+(10 rows)
+
+	ROLLBACK;
+	BEGIN;
+		FETCH 10 FROM c;
+ unique2 
+---------
+      10
+      11
+      12
+      13
+      14
+      15
+      16
+      17
+      18
+      19
+(10 rows)
+
+	COMMIT;
+	FETCH 10 FROM c;
+ unique2 
+---------
+      20
+      21
+      22
+      23
+      24
+      25
+      26
+      27
+      28
+      29
+(10 rows)
+
+	CLOSE c;
+	DECLARE c CURSOR FOR SELECT unique2/0 FROM tenk1;
+	BEGIN;
+		FETCH 10 FROM c;
+ERROR:  division by zero
+	ROLLBACK;
+	-- c is now dead to the world ...
+	BEGIN;
+		FETCH 10 FROM c;
+ERROR:  portal "c" cannot be run
+	ROLLBACK;
+	FETCH 10 FROM c;
+ERROR:  portal "c" cannot be run
+COMMIT;
 DROP TABLE foo;
 DROP TABLE baz;
 DROP TABLE barbaz;
diff --git a/src/test/regress/sql/transactions.sql b/src/test/regress/sql/transactions.sql
index 5af024fdfe6..f2a206979fe 100644
--- a/src/test/regress/sql/transactions.sql
+++ b/src/test/regress/sql/transactions.sql
@@ -127,6 +127,28 @@ BEGIN;
 COMMIT;
 SELECT 1;			-- this should work
 
+-- check non-transactional behavior of cursors
+BEGIN;
+	DECLARE c CURSOR FOR SELECT unique2 FROM tenk1;
+	BEGIN;
+		FETCH 10 FROM c;
+	ROLLBACK;
+	BEGIN;
+		FETCH 10 FROM c;
+	COMMIT;
+	FETCH 10 FROM c;
+	CLOSE c;
+	DECLARE c CURSOR FOR SELECT unique2/0 FROM tenk1;
+	BEGIN;
+		FETCH 10 FROM c;
+	ROLLBACK;
+	-- c is now dead to the world ...
+	BEGIN;
+		FETCH 10 FROM c;
+	ROLLBACK;
+	FETCH 10 FROM c;
+COMMIT;
+
 
 DROP TABLE foo;
 DROP TABLE baz;