Fix the mechanism for reporting the original table OID and column number

of columns of a query result so that it can "see through" cursors and
prepared statements.  Per gripe a couple months back from John DeSoi.
This commit is contained in:
Tom Lane 2005-06-22 17:45:46 +00:00
parent 84d73a6dbc
commit e98edb5555
6 changed files with 121 additions and 34 deletions

View File

@ -9,7 +9,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/common/printtup.c,v 1.90 2005/05/01 18:56:17 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/common/printtup.c,v 1.91 2005/06/22 17:45:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -19,6 +19,7 @@
#include "access/printtup.h"
#include "libpq/libpq.h"
#include "libpq/pqformat.h"
#include "tcop/pquery.h"
#include "utils/lsyscache.h"
#include "utils/portal.h"
@ -130,16 +131,9 @@ printtup_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
* descriptions, then we send back the tuple descriptor of the tuples.
*/
if (operation == CMD_SELECT && myState->sendDescrip)
{
List *targetlist;
if (portal->strategy == PORTAL_ONE_SELECT)
targetlist = ((Query *) linitial(portal->parseTrees))->targetList;
else
targetlist = NIL;
SendRowDescriptionMessage(typeinfo, targetlist, portal->formats);
}
SendRowDescriptionMessage(typeinfo,
FetchPortalTargetList(portal),
portal->formats);
/* ----------------
* We could set up the derived attr info at this time, but we postpone it

View File

@ -10,7 +10,7 @@
* Copyright (c) 2002-2005, PostgreSQL Global Development Group
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.39 2005/06/03 23:05:28 tgl Exp $
* $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.40 2005/06/22 17:45:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -445,6 +445,58 @@ FetchPreparedStatementResultDesc(PreparedStatement *stmt)
return NULL;
}
/*
* Given a prepared statement that returns tuples, extract the query
* targetlist. Returns NIL if the statement doesn't have a determinable
* targetlist.
*
* Note: do not modify the result.
*
* XXX be careful to keep this in sync with FetchPortalTargetList,
* and with UtilityReturnsTuples.
*/
List *
FetchPreparedStatementTargetList(PreparedStatement *stmt)
{
PortalStrategy strategy = ChoosePortalStrategy(stmt->query_list);
if (strategy == PORTAL_ONE_SELECT)
return ((Query *) linitial(stmt->query_list))->targetList;
if (strategy == PORTAL_UTIL_SELECT)
{
Node *utilityStmt;
utilityStmt = ((Query *) linitial(stmt->query_list))->utilityStmt;
switch (nodeTag(utilityStmt))
{
case T_FetchStmt:
{
FetchStmt *substmt = (FetchStmt *) utilityStmt;
Portal subportal;
Assert(!substmt->ismove);
subportal = GetPortalByName(substmt->portalname);
Assert(PortalIsValid(subportal));
return FetchPortalTargetList(subportal);
}
case T_ExecuteStmt:
{
ExecuteStmt *substmt = (ExecuteStmt *) utilityStmt;
PreparedStatement *entry;
Assert(!substmt->into);
entry = FetchPreparedStatement(substmt->name, true);
return FetchPreparedStatementTargetList(entry);
}
default:
break;
}
}
return NIL;
}
/*
* Implements the 'DEALLOCATE' utility statement: deletes the
* specified plan from storage.

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.449 2005/06/17 22:32:46 tgl Exp $
* $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.450 2005/06/22 17:45:45 tgl Exp $
*
* NOTES
* this is the "main" module of the postgres backend and
@ -1928,15 +1928,9 @@ exec_describe_statement_message(const char *stmt_name)
*/
tupdesc = FetchPreparedStatementResultDesc(pstmt);
if (tupdesc)
{
List *targetlist;
if (ChoosePortalStrategy(pstmt->query_list) == PORTAL_ONE_SELECT)
targetlist = ((Query *) linitial(pstmt->query_list))->targetList;
else
targetlist = NIL;
SendRowDescriptionMessage(tupdesc, targetlist, NULL);
}
SendRowDescriptionMessage(tupdesc,
FetchPreparedStatementTargetList(pstmt),
NULL);
else
pq_putemptymessage('n'); /* NoData */
@ -1962,16 +1956,9 @@ exec_describe_portal_message(const char *portal_name)
return; /* can't actually do anything... */
if (portal->tupDesc)
{
List *targetlist;
if (portal->strategy == PORTAL_ONE_SELECT)
targetlist = ((Query *) linitial(portal->parseTrees))->targetList;
else
targetlist = NIL;
SendRowDescriptionMessage(portal->tupDesc, targetlist,
SendRowDescriptionMessage(portal->tupDesc,
FetchPortalTargetList(portal),
portal->formats);
}
else
pq_putemptymessage('n'); /* NoData */
}

View File

@ -8,13 +8,14 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/tcop/pquery.c,v 1.93 2005/03/25 21:57:58 tgl Exp $
* $PostgreSQL: pgsql/src/backend/tcop/pquery.c,v 1.94 2005/06/22 17:45:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "commands/prepare.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "miscadmin.h"
@ -252,6 +253,56 @@ ChoosePortalStrategy(List *parseTrees)
return strategy;
}
/*
* FetchPortalTargetList
* Given a portal that returns tuples, extract the query targetlist.
* Returns NIL if the portal doesn't have a determinable targetlist.
*
* Note: do not modify the result.
*
* XXX be careful to keep this in sync with FetchPreparedStatementTargetList,
* and with UtilityReturnsTuples.
*/
List *
FetchPortalTargetList(Portal portal)
{
if (portal->strategy == PORTAL_ONE_SELECT)
return ((Query *) linitial(portal->parseTrees))->targetList;
if (portal->strategy == PORTAL_UTIL_SELECT)
{
Node *utilityStmt;
utilityStmt = ((Query *) linitial(portal->parseTrees))->utilityStmt;
switch (nodeTag(utilityStmt))
{
case T_FetchStmt:
{
FetchStmt *substmt = (FetchStmt *) utilityStmt;
Portal subportal;
Assert(!substmt->ismove);
subportal = GetPortalByName(substmt->portalname);
Assert(PortalIsValid(subportal));
return FetchPortalTargetList(subportal);
}
case T_ExecuteStmt:
{
ExecuteStmt *substmt = (ExecuteStmt *) utilityStmt;
PreparedStatement *entry;
Assert(!substmt->into);
entry = FetchPreparedStatement(substmt->name, true);
return FetchPreparedStatementTargetList(entry);
}
default:
break;
}
}
return NIL;
}
/*
* PortalStart
* Prepare a portal for execution.

View File

@ -6,7 +6,7 @@
*
* Copyright (c) 2002-2005, PostgreSQL Global Development Group
*
* $PostgreSQL: pgsql/src/include/commands/prepare.h,v 1.13 2005/01/01 05:43:09 momjian Exp $
* $PostgreSQL: pgsql/src/include/commands/prepare.h,v 1.14 2005/06/22 17:45:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -59,5 +59,6 @@ extern PreparedStatement *FetchPreparedStatement(const char *stmt_name,
extern void DropPreparedStatement(const char *stmt_name, bool showError);
extern List *FetchPreparedStatementParams(const char *stmt_name);
extern TupleDesc FetchPreparedStatementResultDesc(PreparedStatement *stmt);
extern List *FetchPreparedStatementTargetList(PreparedStatement *stmt);
#endif /* PREPARE_H */

View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/tcop/pquery.h,v 1.34 2004/12/31 22:03:44 pgsql Exp $
* $PostgreSQL: pgsql/src/include/tcop/pquery.h,v 1.35 2005/06/22 17:45:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -22,6 +22,8 @@ extern DLLIMPORT Portal ActivePortal;
extern PortalStrategy ChoosePortalStrategy(List *parseTrees);
extern List *FetchPortalTargetList(Portal portal);
extern void PortalStart(Portal portal, ParamListInfo params,
Snapshot snapshot);