提交 4e5a947d 编写于 作者: B Bruce Momjian

Make MOVE/FETCH 0 actually move/fetch 0. Add MOVE LAST to move to end

of cursor.
上级 9b12ab6d
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/move.sgml,v 1.13 2002/04/21 19:02:39 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/move.sgml,v 1.14 2002/11/13 00:44:08 momjian Exp $
PostgreSQL documentation
-->
......@@ -21,7 +21,8 @@ PostgreSQL documentation
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
MOVE [ <replaceable class="PARAMETER">direction</replaceable> ] [ <replaceable class="PARAMETER">count</replaceable> ]
MOVE [ <replaceable class="PARAMETER">direction</replaceable> ]
{<replaceable class="PARAMETER">count</replaceable> | LAST }
{ IN | FROM } <replaceable class="PARAMETER">cursor</replaceable>
</synopsis>
</refsynopsisdiv>
......@@ -37,8 +38,9 @@ MOVE [ <replaceable class="PARAMETER">direction</replaceable> ] [ <replaceable c
<command>MOVE</command> allows a user to move cursor position a specified
number of rows.
<command>MOVE</command> works like the <command>FETCH</command> command,
but only positions the cursor and does
not return rows.
but only positions the cursor and does not return rows.
<replaceable class="PARAMETER">LAST</replaceable> moves to the end
of the cursor.
</para>
<para>
Refer to
......
......@@ -8,13 +8,15 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/portalcmds.c,v 1.3 2002/09/04 20:31:15 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/commands/portalcmds.c,v 1.4 2002/11/13 00:44:08 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <limits.h>
#include "commands/portalcmds.h"
#include "executor/executor.h"
......@@ -55,7 +57,7 @@ PortalCleanup(Portal portal)
*
* name: name of portal
* forward: forward or backward fetch?
* count: # of tuples to fetch (0 implies all)
* count: # of tuples to fetch
* dest: where to send results
* completionTag: points to a buffer of size COMPLETION_TAG_BUFSIZE
* in which to store a command completion status string.
......@@ -100,6 +102,14 @@ PerformPortalFetch(char *name,
return;
}
/* If zero count, we are done */
if (count == 0)
return;
/* Internally, zero count processes all portal rows */
if (count == INT_MAX)
count = 0;
/*
* switch into the portal context
*/
......
......@@ -27,7 +27,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.185 2002/11/13 00:39:46 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.186 2002/11/13 00:44:08 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -1116,7 +1116,8 @@ lnext: ;
/*
* check our tuple count.. if we've processed the proper number
* then quit, else loop again and process more tuples..
* then quit, else loop again and process more tuples. Zero
* number_tuples means no limit.
*/
current_tuple_count++;
if (numberTuples == current_tuple_count)
......
......@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.376 2002/11/11 22:19:23 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.377 2002/11/13 00:44:08 momjian Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
......@@ -49,6 +49,7 @@
#include "postgres.h"
#include <ctype.h>
#include <limits.h>
#include "access/htup.h"
#include "catalog/index.h"
......@@ -358,7 +359,7 @@ static void doNegateFloat(Value *v);
KEY
LANCOMPILER LANGUAGE LEADING LEFT LEVEL LIKE LIMIT
LANCOMPILER LANGUAGE LAST LEADING LEFT LEVEL LIKE LIMIT
LISTEN LOAD LOCAL LOCALTIME LOCALTIMESTAMP LOCATION
LOCK_P
......@@ -2661,7 +2662,7 @@ FetchStmt: FETCH direction fetch_how_many from_in name
if ($3 < 0)
{
$3 = -$3;
$2 = (($2 == FORWARD)? BACKWARD: FORWARD);
$2 = (($2 == FORWARD) ? BACKWARD: FORWARD);
}
n->direction = $2;
n->howMany = $3;
......@@ -2729,8 +2730,8 @@ direction: FORWARD { $$ = FORWARD; }
fetch_how_many:
Iconst { $$ = $1; }
| '-' Iconst { $$ = - $2; }
/* 0 means fetch all tuples*/
| ALL { $$ = 0; }
| ALL { $$ = INT_MAX; }
| LAST { $$ = INT_MAX; }
| NEXT { $$ = 1; }
| PRIOR { $$ = -1; }
;
......@@ -7060,6 +7061,7 @@ unreserved_keyword:
| KEY
| LANGUAGE
| LANCOMPILER
| LAST
| LEVEL
| LISTEN
| LOAD
......
......@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.129 2002/11/11 22:19:23 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/parser/keywords.c,v 1.130 2002/11/13 00:44:09 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -172,6 +172,7 @@ static const ScanKeyword ScanKeywords[] = {
{"key", KEY},
{"lancompiler", LANCOMPILER},
{"language", LANGUAGE},
{"last", LAST},
{"leading", LEADING},
{"left", LEFT},
{"level", LEVEL},
......
......@@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.180 2002/10/21 20:31:52 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/tcop/utility.c,v 1.181 2002/11/13 00:44:09 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -262,9 +262,8 @@ ProcessUtility(Node *parsetree,
forward = (bool) (stmt->direction == FORWARD);
/*
* parser ensures that count is >= 0 and 'fetch ALL' -> 0
* parser ensures that count is >= 0
*/
count = stmt->howMany;
PerformPortalFetch(portalName, forward, count,
(stmt->ismove) ? None : dest,
......
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: portalcmds.h,v 1.2 2002/09/04 20:31:42 momjian Exp $
* $Id: portalcmds.h,v 1.3 2002/11/13 00:44:09 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -18,7 +18,7 @@
/*
* PerformPortalFetch
* Performs the POSTQUEL function FETCH. Fetches count (or all if 0)
* Performs the POSTQUEL function FETCH. Fetches count
* tuples in portal with name in the forward direction iff goForward.
*
* Exceptions:
......
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: parsenodes.h,v 1.212 2002/11/11 22:19:24 tgl Exp $
* $Id: parsenodes.h,v 1.213 2002/11/13 00:44:09 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -1277,7 +1277,7 @@ typedef struct FetchStmt
{
NodeTag type;
int direction; /* FORWARD or BACKWARD */
int howMany; /* amount to fetch ("ALL" --> 0) */
int howMany; /* amount to fetch */
char *portalname; /* name of portal (cursor) */
bool ismove; /* TRUE if MOVE */
} FetchStmt;
......
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