diff --git a/doc/src/sgml/ref/declare.sgml b/doc/src/sgml/ref/declare.sgml
index f823cf77bbea5a31c1e634871d9bd2953d2aa8ee..269d2c101c4ce9ca18c50df6be5069d613505f60 100644
--- a/doc/src/sgml/ref/declare.sgml
+++ b/doc/src/sgml/ref/declare.sgml
@@ -1,5 +1,5 @@
<!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/declare.sgml,v 1.41 2007/06/11 01:16:21 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/declare.sgml,v 1.42 2007/10/24 23:27:07 tgl Exp $
PostgreSQL documentation
-->
@@ -172,7 +172,7 @@ DECLARE <replaceable class="parameter">name</replaceable> [ BINARY ] [ INSENSITI
transaction. Thus, <command>DECLARE</> without <literal>WITH
HOLD</literal> is useless outside a transaction block: the cursor would
survive only to the completion of the statement. Therefore
- <productname>PostgreSQL</productname> reports an error if this
+ <productname>PostgreSQL</productname> reports an error if such a
command is used outside a transaction block.
Use
<xref linkend="sql-begin" endterm="sql-begin-title">,
@@ -230,6 +230,11 @@ DECLARE <replaceable class="parameter">name</replaceable> [ BINARY ] [ INSENSITI
will have no effect if the row was changed meanwhile.
</para>
+ <para>
+ <literal>SCROLL</literal> may not be specified when the query
+ includes <literal>FOR UPDATE</> or <literal>FOR SHARE</>.
+ </para>
+
<para>
The SQL standard only makes provisions for cursors in embedded
<acronym>SQL</acronym>. The <productname>PostgreSQL</productname>
@@ -265,10 +270,11 @@ DECLARE liahona CURSOR FOR SELECT * FROM films;
<title>Compatibility</title>
<para>
- The SQL standard specifies that by default, cursors are sensitive to
- concurrent updates of the underlying data. In
+ The SQL standard says that it is implementation-dependent whether cursors
+ are sensitive to concurrent updates of the underlying data by default. In
<productname>PostgreSQL</productname>, cursors are insensitive by default,
- and can be made sensitive by specifying <literal>FOR UPDATE</>.
+ and can be made sensitive by specifying <literal>FOR UPDATE</>. Other
+ products may work differently.
</para>
<para>
diff --git a/src/backend/commands/portalcmds.c b/src/backend/commands/portalcmds.c
index 939452650d088428b78c3caa2a4a3462d7719a87..e8f21d4f0836027cd1074c58fc3cc316ba082f54 100644
--- a/src/backend/commands/portalcmds.c
+++ b/src/backend/commands/portalcmds.c
@@ -14,7 +14,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/commands/portalcmds.c,v 1.65 2007/04/27 22:05:47 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/commands/portalcmds.c,v 1.66 2007/10/24 23:27:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -102,12 +102,13 @@ PerformCursorOpen(PlannedStmt *stmt, ParamListInfo params,
*
* If the user didn't specify a SCROLL type, allow or disallow scrolling
* based on whether it would require any additional runtime overhead to do
- * so.
+ * so. Also, we disallow scrolling for FOR UPDATE cursors.
*/
portal->cursorOptions = cstmt->options;
if (!(portal->cursorOptions & (CURSOR_OPT_SCROLL | CURSOR_OPT_NO_SCROLL)))
{
- if (ExecSupportsBackwardScan(stmt->planTree))
+ if (stmt->rowMarks == NIL &&
+ ExecSupportsBackwardScan(stmt->planTree))
portal->cursorOptions |= CURSOR_OPT_SCROLL;
else
portal->cursorOptions |= CURSOR_OPT_NO_SCROLL;
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 875e4da2914e1f73ab40cabe12f1eb1c8faa4678..6d59401d0fb963f176dea5d26f21606b88092d3e 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.181 2007/09/20 17:56:31 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.182 2007/10/24 23:27:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -975,12 +975,29 @@ SPI_cursor_open(const char *name, SPIPlanPtr plan,
{
if (list_length(stmt_list) == 1 &&
IsA((Node *) linitial(stmt_list), PlannedStmt) &&
+ ((PlannedStmt *) linitial(stmt_list))->rowMarks == NIL &&
ExecSupportsBackwardScan(((PlannedStmt *) linitial(stmt_list))->planTree))
portal->cursorOptions |= CURSOR_OPT_SCROLL;
else
portal->cursorOptions |= CURSOR_OPT_NO_SCROLL;
}
+ /*
+ * Disallow SCROLL with SELECT FOR UPDATE. This is not redundant with
+ * the check in transformDeclareCursorStmt because the cursor options
+ * might not have come through there.
+ */
+ if (portal->cursorOptions & CURSOR_OPT_SCROLL)
+ {
+ if (list_length(stmt_list) == 1 &&
+ IsA((Node *) linitial(stmt_list), PlannedStmt) &&
+ ((PlannedStmt *) linitial(stmt_list))->rowMarks != NIL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("DECLARE CURSOR SCROLL ... FOR UPDATE/SHARE is not supported"),
+ errdetail("Scrollable cursors must be READ ONLY.")));
+ }
+
/*
* If told to be read-only, we'd better check for read-only queries.
* This can't be done earlier because we need to look at the finished,
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 3135d8524675545d3d0cc5542b9538065fc890db..567130b18db5947bec9678f94bc843ae1b2db437 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -17,7 +17,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.367 2007/06/23 22:12:51 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.368 2007/10/24 23:27:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -1623,6 +1623,20 @@ transformDeclareCursorStmt(ParseState *pstate, DeclareCursorStmt *stmt)
errmsg("DECLARE CURSOR WITH HOLD ... FOR UPDATE/SHARE is not supported"),
errdetail("Holdable cursors must be READ ONLY.")));
+ /* FOR UPDATE and SCROLL are not compatible */
+ if (result->rowMarks != NIL && (stmt->options & CURSOR_OPT_SCROLL))
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("DECLARE CURSOR SCROLL ... FOR UPDATE/SHARE is not supported"),
+ errdetail("Scrollable cursors must be READ ONLY.")));
+
+ /* FOR UPDATE and INSENSITIVE are not compatible */
+ if (result->rowMarks != NIL && (stmt->options & CURSOR_OPT_INSENSITIVE))
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("DECLARE CURSOR INSENSITIVE ... FOR UPDATE/SHARE is not supported"),
+ errdetail("Insensitive cursors must be READ ONLY.")));
+
/* We won't need the raw querytree any more */
stmt->query = NULL;
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 412fadac54e94784e8207478a55c19608c859185..e1a6198e01250f264b0d12f3d7bbc0e3b21fee3e 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.353 2007/09/03 18:46:30 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/parsenodes.h,v 1.354 2007/10/24 23:27:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -1479,7 +1479,7 @@ typedef struct CommentStmt
#define CURSOR_OPT_BINARY 0x0001 /* BINARY */
#define CURSOR_OPT_SCROLL 0x0002 /* SCROLL explicitly given */
#define CURSOR_OPT_NO_SCROLL 0x0004 /* NO SCROLL explicitly given */
-#define CURSOR_OPT_INSENSITIVE 0x0008 /* INSENSITIVE (unimplemented) */
+#define CURSOR_OPT_INSENSITIVE 0x0008 /* INSENSITIVE */
#define CURSOR_OPT_HOLD 0x0010 /* WITH HOLD */
#define CURSOR_OPT_FAST_PLAN 0x0020 /* prefer fast-start plan */
diff --git a/src/test/regress/expected/portals.out b/src/test/regress/expected/portals.out
index b6673073cdf68da743c248df205f2dae62622827..527550eabde67f910d437674ecb114457484fa00 100644
--- a/src/test/regress/expected/portals.out
+++ b/src/test/regress/expected/portals.out
@@ -1073,40 +1073,31 @@ SELECT * FROM uctest;
23 | three
(2 rows)
--- sensitive cursor should show effects of updates or deletes
--- XXX current behavior is WRONG
-FETCH RELATIVE 0 FROM c1;
+DELETE FROM uctest WHERE CURRENT OF c1;
+SELECT * FROM uctest;
f1 | f2
----+-----
8 | one
(1 row)
-DELETE FROM uctest WHERE CURRENT OF c1;
-SELECT * FROM uctest;
- f1 | f2
-----+-------
- 23 | three
-(1 row)
-
DELETE FROM uctest WHERE CURRENT OF c1; -- no-op
SELECT * FROM uctest;
- f1 | f2
-----+-------
- 23 | three
+ f1 | f2
+----+-----
+ 8 | one
(1 row)
UPDATE uctest SET f1 = f1 + 10 WHERE CURRENT OF c1; -- no-op
SELECT * FROM uctest;
- f1 | f2
-----+-------
- 23 | three
+ f1 | f2
+----+-----
+ 8 | one
(1 row)
+--- sensitive cursors can't currently scroll back, so this is an error:
FETCH RELATIVE 0 FROM c1;
- f1 | f2
-----+----
-(0 rows)
-
+ERROR: cursor can only scan forward
+HINT: Declare it with SCROLL option to enable backward scan.
ROLLBACK;
SELECT * FROM uctest;
f1 | f2
diff --git a/src/test/regress/sql/portals.sql b/src/test/regress/sql/portals.sql
index bdf5956d69ca4e68195287f579e5e80a28f7dcaa..8275ed78c84647ffb780bc71272122eaf43ae9ed 100644
--- a/src/test/regress/sql/portals.sql
+++ b/src/test/regress/sql/portals.sql
@@ -376,15 +376,13 @@ UPDATE uctest SET f1 = f1 + 10 WHERE CURRENT OF c1;
SELECT * FROM uctest;
UPDATE uctest SET f1 = f1 + 10 WHERE CURRENT OF c1;
SELECT * FROM uctest;
--- sensitive cursor should show effects of updates or deletes
--- XXX current behavior is WRONG
-FETCH RELATIVE 0 FROM c1;
DELETE FROM uctest WHERE CURRENT OF c1;
SELECT * FROM uctest;
DELETE FROM uctest WHERE CURRENT OF c1; -- no-op
SELECT * FROM uctest;
UPDATE uctest SET f1 = f1 + 10 WHERE CURRENT OF c1; -- no-op
SELECT * FROM uctest;
+--- sensitive cursors can't currently scroll back, so this is an error:
FETCH RELATIVE 0 FROM c1;
ROLLBACK;
SELECT * FROM uctest;