DBLink patch

Your patch has been added to the PostgreSQL unapplied patches list at:

http://momjian.postgresql.org/cgi-bin/pgpatches

I will try to apply it within the next 48 hours.

---------------------------------------------------------------------------

Shridhar Daithankar wrote:
Content-Description: Mail message body

Hello,

Please apply attached patch to contrib/dblink. It adds named persistent
connections to dblink.

I have been working on this with Joe Conway and this patch is seems to work
without any problem.

Thanks Joe, for your assistance.

Bye
Shridhar

--
Anthony's Law of the Workshop: Any tool when dropped, will roll into the least
accessible corner of the workshop.Corollary: On the way to the corner, any
dropped tool will first strike your toes.

Content-Description: Text from file 'dblink.02.diff'

Index: contrib/dblink/README.dblink
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/README.dblink,v
retrieving revision 1.7
diff -c -r1.7 README.dblink
*** contrib/dblink/README.dblink	23 Nov 2002 18:59:25 -0000	1.7
--- contrib/dblink/README.dblink	15 Jun 2003 05:17:46 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
* 
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
* 
* Permission to use, copy, modify, and distribute this software and its
***************
*** 27,40 ****
*
*/

! Version 0.5 (25 August, 2002):
! Major overhaul to work with new backend "table function" capability. Removed
! dblink_strtok() and dblink_replace() functions because they are now
! available as backend functions (split() and replace() respectively).
! Tested under Linux (Red Hat 7.3) and PostgreSQL 7.3devel. This version
! is no longer backwards portable to PostgreSQL 7.2.

Release Notes:
Version 0.5
- dblink now supports use directly as a table function; this is the new
preferred usage going forward
--- 30,45 ----
*
*/

! Version 0.6 (14 June, 2003):
! Completely removed previously deprecated functions. Added ability
! to create "named" persistent connections in addition to the single global
! "unnamed" persistent connection.
! Tested under Linux (Red Hat 9) and PostgreSQL 7.4devel.

Release Notes:
+   Version 0.6
+     - functions deprecated in 0.5 have been removed
+     - added ability to create "named" persistent connections
Version 0.5
- dblink now supports use directly as a table function; this is the new
preferred usage going forward
***************
*** 87,121 ****
connection
------------
dblink_connect(text) RETURNS text
!        - opens a connection that will persist for duration of current
backend or until it is disconnected
dblink_disconnect() RETURNS text
!        - disconnects a persistent connection

cursor
------------
dblink_open(text,text) RETURNS text
! - opens a cursor using connection already opened with dblink_connect()
! that will persist for duration of current backend or until it is
! closed
dblink_fetch(text, int) RETURNS setof record
! - fetches data from an already opened cursor
dblink_close(text) RETURNS text
! - closes a cursor

query
------------
dblink(text,text) RETURNS setof record
! - returns a set of results from remote SELECT query
! (Note: comment out in dblink.sql to use deprecated version)
dblink(text) RETURNS setof record
! - returns a set of results from remote SELECT query, using connection
! already opened with dblink_connect()

execute
------------
dblink_exec(text, text) RETURNS text
!        - executes an INSERT/UPDATE/DELETE query remotely
dblink_exec(text) RETURNS text
- executes an INSERT/UPDATE/DELETE query remotely, using connection
already opened with dblink_connect()
--- 92,142 ----
connection
------------
dblink_connect(text) RETURNS text
!        - opens an unnamed connection that will persist for duration of
!          current backend or until it is disconnected
!      dblink_connect(text,text) RETURNS text
!        - opens a named connection that will persist for duration of current
backend or until it is disconnected
dblink_disconnect() RETURNS text
!        - disconnects the unnamed persistent connection
!      dblink_disconnect(text) RETURNS text
!        - disconnects a named persistent connection

cursor
------------
dblink_open(text,text) RETURNS text
! - opens a cursor using unnamed connection already opened with
! dblink_connect() that will persist for duration of current backend
! or until it is closed
! dblink_open(text,text,text) RETURNS text
! - opens a cursor using a named connection already opened with
! dblink_connect() that will persist for duration of current backend
! or until it is closed
dblink_fetch(text, int) RETURNS setof record
! - fetches data from an already opened cursor on the unnamed connection
! dblink_fetch(text, text, int) RETURNS setof record
! - fetches data from an already opened cursor on a named connection
dblink_close(text) RETURNS text
! - closes a cursor on the unnamed connection
! dblink_close(text,text) RETURNS text
! - closes a cursor on a named connection

query
------------
dblink(text,text) RETURNS setof record
! - returns a set of results from remote SELECT query; the first argument
! is either a connection string, or the name of an already opened
! persistant connection
dblink(text) RETURNS setof record
! - returns a set of results from remote SELECT query, using the unnamed
! connection already opened with dblink_connect()

execute
------------
dblink_exec(text, text) RETURNS text
! - executes an INSERT/UPDATE/DELETE query remotely; the first argument
! is either a connection string, or the name of an already opened
! persistant connection
dblink_exec(text) RETURNS text
- executes an INSERT/UPDATE/DELETE query remotely, using connection
already opened with dblink_connect()
***************
*** 135,153 ****
dblink_build_sql_update(text,int2vector,int2,_text,_text) RETURNS text
- builds an update statement using a local tuple, replacing the
selection key field values with alternate supplied values
-
- Not installed by default
- deprecated
- ------------
- dblink(text,text) RETURNS setof int
- - *DEPRECATED* returns a resource id for results from remote query
- (Note: must uncomment in dblink.sql to use)
- dblink_tok(int,int) RETURNS text
- - *DEPRECATED* extracts and returns individual field results; used
- only in conjunction with the *DEPRECATED* form of dblink
- (Note: must uncomment in dblink.sql to use)
- dblink_last_oid(int) RETURNS oid
- - *DEPRECATED* returns the last inserted oid

Documentation:

--- 156,161 ----
Index: contrib/dblink/dblink.c
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.c,v
retrieving revision 1.20
diff -c -r1.20 dblink.c
*** contrib/dblink/dblink.c	28 May 2003 16:03:55 -0000	1.20
--- contrib/dblink/dblink.c	15 Jun 2003 04:17:52 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
***************
*** 27,35 ****
*
*/
#include "postgres.h"
- 
#include "libpq-fe.h"
- 
#include "fmgr.h"
#include "funcapi.h"
#include "access/tupdesc.h"
--- 30,36 ----
***************
*** 51,63 ****
#include "utils/array.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"

#include "dblink.h"

/*
* Internal declarations
*/
! static dblink_results *init_dblink_results(MemoryContext fn_mcxt);
static char **get_pkey_attnames(Oid relid, int16 *numatts);
static char *get_sql_insert(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals, char **tgt_pkattvals);
static char *get_sql_delete(Oid relid, int16 *pkattnums, int16 pknumatts, char **tgt_pkattvals);
--- 52,78 ----
#include "utils/array.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
+ #include "utils/palloc.h"
+ #include "utils/dynahash.h"
+ #include "utils/hsearch.h"
+ #include "utils/memutils.h"

#include "dblink.h"

+ typedef struct remoteConn
+ {
+ 	PGconn *con;			/* Hold the remote connection */
+ 	bool remoteTrFlag;		/* Indicates whether or not a transaction
+ 							 * on remote database is in progress*/
+ } remoteConn;
+ 
/*
* Internal declarations
*/
! static remoteConn *getConnectionByName(const char *name);
! static HTAB *createConnHash(void);
! static bool createNewConnection(const char *name,remoteConn *con);
! static void deleteConnection(const char *name);
static char **get_pkey_attnames(Oid relid, int16 *numatts);
static char *get_sql_insert(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals, char **tgt_pkattvals);
static char *get_sql_delete(Oid relid, int16 *pkattnums, int16 pknumatts, char **tgt_pkattvals);
***************
*** 67,83 ****
static int16 get_attnum_pk_pos(int16 *pkattnums, int16 pknumatts, int16 key);
static HeapTuple get_tuple_of_interest(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals);
static Oid	get_relid_from_relname(text *relname_text);
- static dblink_results *get_res_ptr(int32 res_id_index);
- static void append_res_ptr(dblink_results * results);
- static void remove_res_ptr(dblink_results * results);
static TupleDesc pgresultGetTupleDesc(PGresult *res);
static char *generate_relation_name(Oid relid);

/* Global */
! List *res_id = NIL;
! int res_id_index = 0;
! PGconn *persistent_conn = NULL;

#define GET_TEXT(cstrp) DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(cstrp)))
#define GET_STR(textp) DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(textp)))
#define xpfree(var_) \
--- 82,113 ----
static int16 get_attnum_pk_pos(int16 *pkattnums, int16 pknumatts, int16 key);
static HeapTuple get_tuple_of_interest(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals);
static Oid	get_relid_from_relname(text *relname_text);
static TupleDesc pgresultGetTupleDesc(PGresult *res);
static char *generate_relation_name(Oid relid);

/* Global */
! List *res_id = NIL;
! int res_id_index = 0;
! PGconn *persistent_conn = NULL;
! static HTAB *remoteConnHash=NULL;
!
! /*
! Following is list that holds multiple remote connections.
! Calling convention of each dblink function changes to accept
! connection name as the first parameter. The connection list is
! much like ecpg e.g. a mapping between a name and a PGconn object.
! */
!
! typedef struct remoteConnHashEnt
! {
! char name[NAMEDATALEN];
! remoteConn *rcon;
! } remoteConnHashEnt;
!
! /* initial number of connection hashes */
! #define NUMCONN 16

+ /* general utility */
#define GET_TEXT(cstrp) DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(cstrp)))
#define GET_STR(textp) DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(textp)))
#define xpfree(var_) \
***************
*** 88,93 ****
--- 118,158 ----
var_ = NULL; \
} \
} while (0)
+ #define DBLINK_RES_ERROR(p1, p2) \
+ 	do { \
+ 			msg = pstrdup(PQerrorMessage(conn)); \
+ 			if (res) \
+ 				PQclear(res); \
+ 			elog(ERROR, "%s: %s: %s", p1, p2, msg); \
+ 	} while (0)
+ #define DBLINK_CONN_NOT_AVAIL(p1) \
+ 	do { \
+ 		if(conname) \
+ 			elog(ERROR, "%s: connection %s not available", p1, conname); \
+ 		else \
+ 			elog(ERROR, "%s: connection not available", p1); \
+ 	} while (0)
+ #define DBLINK_GET_CONN(p1) \
+ 	do { \
+ 			char *conname_or_str = GET_STR(PG_GETARG_TEXT_P(0)); \
+ 			rcon = getConnectionByName(conname_or_str); \
+ 			if(rcon) \
+ 			{ \
+ 				conn = rcon->con; \
+ 				freeconn = false; \
+ 			} \
+ 			else \
+ 			{ \
+ 				connstr = conname_or_str; \
+ 				conn = PQconnectdb(connstr); \
+ 				if (PQstatus(conn) == CONNECTION_BAD) \
+ 				{ \
+ 					msg = pstrdup(PQerrorMessage(conn)); \
+ 					PQfinish(conn); \
+ 					elog(ERROR, "%s: connection error: %s", p1, msg); \
+ 				} \
+ 			} \
+ 	} while (0)

/*
***************
*** 97,124 ****
Datum
dblink_connect(PG_FUNCTION_ARGS)
{
! char *connstr = GET_STR(PG_GETARG_TEXT_P(0));
char *msg;
- text *result_text;
MemoryContext oldcontext;

! if (persistent_conn != NULL)
! PQfinish(persistent_conn);

oldcontext = MemoryContextSwitchTo(TopMemoryContext);
! persistent_conn = PQconnectdb(connstr);
MemoryContextSwitchTo(oldcontext);

! if (PQstatus(persistent_conn) == CONNECTION_BAD)
{
! msg = pstrdup(PQerrorMessage(persistent_conn));
! PQfinish(persistent_conn);
! persistent_conn = NULL;
elog(ERROR, "dblink_connect: connection error: %s", msg);
}

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 162,213 ----
Datum
dblink_connect(PG_FUNCTION_ARGS)
{
! 	char	   *connstr = NULL;
! 	char	   *connname = NULL;
char	   *msg;
MemoryContext oldcontext;
+ 	PGconn	   *conn = NULL;
+ 	remoteConn *rcon = NULL;

! if(PG_NARGS()==2)
! {
! connstr = GET_STR(PG_GETARG_TEXT_P(1));
! connname = GET_STR(PG_GETARG_TEXT_P(0));
! }
! else if(PG_NARGS()==1)
! connstr = GET_STR(PG_GETARG_TEXT_P(0));

oldcontext = MemoryContextSwitchTo(TopMemoryContext);
!
! if(connname)
! rcon=(remoteConn *) palloc(sizeof(remoteConn));
! conn = PQconnectdb(connstr);
!
MemoryContextSwitchTo(oldcontext);

! if (PQstatus(conn) == CONNECTION_BAD)
{
! msg = pstrdup(PQerrorMessage(conn));
! PQfinish(conn);
! if(rcon)
! pfree(rcon);
elog(ERROR, "dblink_connect: connection error: %s", msg);
}

! if(connname)
! {
! rcon->con = conn;
! if(createNewConnection(connname, rcon) == false)
! {
! PQfinish(conn);
! pfree(rcon);
! elog(ERROR, "dblink_connect: cannot save named connection");
! }
! }
! else
! persistent_conn = conn;
!
! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 128,142 ****
Datum
dblink_disconnect(PG_FUNCTION_ARGS)
{
! text *result_text;

! if (persistent_conn != NULL)
! PQfinish(persistent_conn);

! persistent_conn = NULL;

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 217,253 ----
Datum
dblink_disconnect(PG_FUNCTION_ARGS)
{
! 	char	   *str = NULL;
! 	remoteConn *rcon = NULL;
! 	PGconn	   *conn = NULL;
! 
! 	if (PG_NARGS() ==1 )
! 	{
! 		str = GET_STR(PG_GETARG_TEXT_P(0));
! 		rcon = getConnectionByName(str);
! 		if (rcon)
! 			conn = rcon->con;
! 	}
! 	else
! 		conn = persistent_conn;

! if (!conn)
! {
! if (str)
! elog(ERROR,"dblink_disconnect: connection named \"%s\" not found",
! str);
! else
! elog(ERROR,"dblink_disconnect: connection not found");
! }

! PQfinish(conn);
! if (rcon)
! {
! deleteConnection(str);
! pfree(rcon);
! }

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 149,175 ****
char *msg;
PGresult *res = NULL;
PGconn *conn = NULL;
! text *result_text;
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
! char *sql = GET_STR(PG_GETARG_TEXT_P(1));
StringInfo str = makeStringInfo();

! if (persistent_conn != NULL)
conn = persistent_conn;
! else
! elog(ERROR, "dblink_open: no connection available");

res = PQexec(conn, "BEGIN");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(conn);
! persistent_conn = NULL;

- elog(ERROR, "dblink_open: begin error: %s", msg);
- }
PQclear(res);

appendStringInfo(str, "DECLARE %s CURSOR FOR %s", curname, sql);
--- 260,294 ----
char	   *msg;
PGresult   *res = NULL;
PGconn	   *conn = NULL;
! 	char	   *curname = NULL;
! 	char	   *sql = NULL;
! 	char	   *conname = NULL;
StringInfo	str = makeStringInfo();
+ 	remoteConn *rcon = NULL;

! if(PG_NARGS() == 2)
! {
! curname = GET_STR(PG_GETARG_TEXT_P(0));
! sql = GET_STR(PG_GETARG_TEXT_P(1));
conn = persistent_conn;
! }
! else if(PG_NARGS() == 3)
! {
! conname = GET_STR(PG_GETARG_TEXT_P(0));
! curname = GET_STR(PG_GETARG_TEXT_P(1));
! sql = GET_STR(PG_GETARG_TEXT_P(2));
! rcon = getConnectionByName(conname);
! if (rcon)
! conn = rcon->con;
! }
!
! if (!conn)
! DBLINK_CONN_NOT_AVAIL("dblink_open");

res = PQexec(conn, "BEGIN");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_open", "begin error");

PQclear(res);

appendStringInfo(str, "DECLARE %s CURSOR FOR %s", curname, sql);
***************
*** 177,195 ****
if (!res ||
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
! {
! msg = pstrdup(PQerrorMessage(conn));
!
! PQclear(res);

! PQfinish(conn);
! persistent_conn = NULL;
!
! elog(ERROR, "dblink: sql error: %s", msg);
! }

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 296,306 ----
if (!res ||
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
! 		DBLINK_RES_ERROR("dblink_open", "sql error");

! PQclear(res);

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 201,249 ****
{
PGconn *conn = NULL;
PGresult *res = NULL;
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
StringInfo str = makeStringInfo();
- text *result_text;
char *msg;

! if (persistent_conn != NULL)
conn = persistent_conn;
! else
! elog(ERROR, "dblink_close: no connection available");

appendStringInfo(str, "CLOSE %s", curname);

/* close the cursor */
res = PQexec(conn, str->data);
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(persistent_conn);
! persistent_conn = NULL;
!
! elog(ERROR, "dblink_close: sql error: %s", msg);
! }

PQclear(res);

/* commit the transaction */
res = PQexec(conn, "COMMIT");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(persistent_conn);
! persistent_conn = NULL;

- elog(ERROR, "dblink_close: commit error: %s", msg);
- }
PQclear(res);

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 312,357 ----
{
PGconn	   *conn = NULL;
PGresult   *res = NULL;
! 	char	   *curname = NULL;
! 	char	   *conname = NULL;
StringInfo	str = makeStringInfo();
char	   *msg;
+ 	remoteConn *rcon = NULL;

! if (PG_NARGS() == 1)
! {
! curname = GET_STR(PG_GETARG_TEXT_P(0));
conn = persistent_conn;
! }
! else if (PG_NARGS()==2)
! {
! conname = GET_STR(PG_GETARG_TEXT_P(0));
! curname = GET_STR(PG_GETARG_TEXT_P(1));
! rcon = getConnectionByName(conname);
! if(rcon)
! conn = rcon->con;
! }
!
! if (!conn)
! DBLINK_CONN_NOT_AVAIL("dblink_close");

appendStringInfo(str, "CLOSE %s", curname);

/* close the cursor */
res = PQexec(conn, str->data);
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_close", "sql error");

PQclear(res);

/* commit the transaction */
res = PQexec(conn, "COMMIT");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_close", "commit error");

PQclear(res);

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 262,267 ****
--- 370,377 ----
char	   *msg;
PGresult   *res = NULL;
MemoryContext oldcontext;
+ 	char	   *conname = NULL;
+ 	remoteConn *rcon=NULL;

/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
***************
*** 271,278 ****
Oid funcid = fcinfo->flinfo->fn_oid;
PGconn *conn = NULL;
StringInfo str = makeStringInfo();
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
! int howmany = PG_GETARG_INT32(1);

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
--- 381,408 ----
Oid			funcid = fcinfo->flinfo->fn_oid;
PGconn	   *conn = NULL;
StringInfo	str = makeStringInfo();
! 		char	   *curname = NULL;
! 		int			howmany = 0;
! 
! 		if (PG_NARGS() == 3)
! 		{
! 			conname = GET_STR(PG_GETARG_TEXT_P(0));
! 			curname = GET_STR(PG_GETARG_TEXT_P(1));
! 			howmany = PG_GETARG_INT32(2);
! 
! 			rcon = getConnectionByName(conname);
! 			if(rcon)
! 				conn = rcon->con;
! 		}
! 		else if (PG_NARGS() == 2)
! 		{
! 			curname = GET_STR(PG_GETARG_TEXT_P(0));
! 			howmany = PG_GETARG_INT32(1);
! 			conn = persistent_conn;
! 		}
! 
! 		if(!conn)
! 			DBLINK_CONN_NOT_AVAIL("dblink_fetch");

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
***************
*** 283,293 ****
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink_fetch: no connection available");
-
appendStringInfo(str, "FETCH %d FROM %s", howmany, curname);

res = PQexec(conn, str->data);
--- 413,418 ----
***************
*** 295,313 ****
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
{
! 			msg = pstrdup(PQerrorMessage(conn));
! 			PQclear(res);
! 
! 			PQfinish(persistent_conn);
! 			persistent_conn = NULL;
! 
! 			elog(ERROR, "dblink_fetch: sql error: %s", msg);
}
else if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
/* cursor does not exist - closed already or bad name */
PQclear(res);
! 			elog(ERROR, "dblink_fetch: cursor %s does not exist", curname);
}

funcctx->max_calls = PQntuples(res);
--- 420,432 ----
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
{
! 			DBLINK_RES_ERROR("dblink_fetch", "sql error");
}
else if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
/* cursor does not exist - closed already or bad name */
PQclear(res);
! 			elog(ERROR, "dblink_fetch: cursor not found: %s", curname);
}

funcctx->max_calls = PQntuples(res);
***************
*** 382,389 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
{
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
--- 501,508 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
+ 		/* do when there is no more left */
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
***************
*** 407,412 ****
--- 526,532 ----
bool		is_sql_cmd = false;
char	   *sql_cmd_status = NULL;
MemoryContext oldcontext;
+ 	bool		freeconn = true;

/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
***************
*** 417,422 ****
--- 537,544 ----
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;
+ 		char	   *conname = NULL;
+ 		remoteConn *rcon=NULL;

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
***************
*** 427,496 ****
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

! if (fcinfo->nargs == 2)
{
! connstr = GET_STR(PG_GETARG_TEXT_P(0));
sql = GET_STR(PG_GETARG_TEXT_P(1));
-
- conn = PQconnectdb(connstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink: connection error: %s", msg);
- }
}
! else if (fcinfo->nargs == 1)
{
sql = GET_STR(PG_GETARG_TEXT_P(0));
-
- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink: no connection available");
}
else
elog(ERROR, "dblink: wrong number of arguments");

res = PQexec(conn, sql);
if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
{
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
! PQfinish(conn);
! if (fcinfo->nargs == 1)
! persistent_conn = NULL;

! elog(ERROR, "dblink: sql error: %s", msg);
}
else
! {
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
! {
! is_sql_cmd = true;

! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);
!
! /*
! * and save a copy of the command status string to return
! * as our result tuple
! */
! sql_cmd_status = PQcmdStatus(res);
! funcctx->max_calls = 1;
! }
! else
! funcctx->max_calls = PQntuples(res);
!
! /* got results, keep track of them */
! funcctx->user_fctx = res;

! /* if needed, close the connection to the database and cleanup */
! if (fcinfo->nargs == 2)
! PQfinish(conn);
! }

/* fast track when no results */
if (funcctx->max_calls < 1)
--- 549,599 ----
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

! if (PG_NARGS() == 2)
{
! DBLINK_GET_CONN("dblink");
sql = GET_STR(PG_GETARG_TEXT_P(1));
}
! else if (PG_NARGS() == 1)
{
+ conn = persistent_conn;
sql = GET_STR(PG_GETARG_TEXT_P(0));
}
else
elog(ERROR, "dblink: wrong number of arguments");

+ 		if(!conn)
+ 			DBLINK_CONN_NOT_AVAIL("dblink_record");
+ 
res = PQexec(conn, sql);
if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
+ 			DBLINK_RES_ERROR("dblink", "sql error");
+ 
+ 		if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
! 			is_sql_cmd = true;
! 
! 			/* need a tuple descriptor representing one TEXT column */
! 			tupdesc = CreateTemplateTupleDesc(1, false);
! 			TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! 							   TEXTOID, -1, 0, false);

! /*
! * and save a copy of the command status string to return
! * as our result tuple
! */
! sql_cmd_status = PQcmdStatus(res);
! funcctx->max_calls = 1;
}
else
! funcctx->max_calls = PQntuples(res);

! /* got results, keep track of them */
! funcctx->user_fctx = res;

! /* if needed, close the connection to the database and cleanup */
! if (freeconn && PG_NARGS() == 2)
! PQfinish(conn);

/* fast track when no results */
if (funcctx->max_calls < 1)
***************
*** 571,578 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
{
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
--- 674,681 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
+ 		/* do when there is no more left */
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
***************
*** 587,858 ****
{
char	   *msg;
PGresult   *res = NULL;
! 	char	   *sql_cmd_status = NULL;
TupleDesc	tupdesc = NULL;
- 	text	   *result_text;
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;

! if (fcinfo->nargs == 2)
{
! connstr = GET_STR(PG_GETARG_TEXT_P(0));
sql = GET_STR(PG_GETARG_TEXT_P(1));
-
- conn = PQconnectdb(connstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink_exec: connection error: %s", msg);
- }
}
! else if (fcinfo->nargs == 1)
{
sql = GET_STR(PG_GETARG_TEXT_P(0));
-
- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink_exec: no connection available");
}
else
elog(ERROR, "dblink_exec: wrong number of arguments");

res = PQexec(conn, sql);
! if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
{
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
! PQfinish(conn);
! if (fcinfo->nargs == 1)
! persistent_conn = NULL;

! elog(ERROR, "dblink_exec: sql error: %s", msg);
}
else
! {
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
! {
! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);

- /*
- * and save a copy of the command status string to return as
- * our result tuple
- */
- sql_cmd_status = PQcmdStatus(res);
- }
- else
- elog(ERROR, "dblink_exec: queries returning results not allowed");
- }
PQclear(res);

/* if needed, close the connection to the database and cleanup */
! if (fcinfo->nargs == 2)
PQfinish(conn);

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql_cmd_status)));
! PG_RETURN_TEXT_P(result_text);
}

- /*
- * Note: this original version of dblink is DEPRECATED;
- * it *will* be removed in favor of the new version on next release
- */
- PG_FUNCTION_INFO_V1(dblink);
- Datum
- dblink(PG_FUNCTION_ARGS)
- {
- PGconn *conn = NULL;
- PGresult *res = NULL;
- dblink_results *results;
- char *optstr;
- char *sqlstatement;
- char *execstatement;
- char *msg;
- int ntuples = 0;
- ReturnSetInfo *rsi;
-
- if (fcinfo->resultinfo == NULL || !IsA(fcinfo->resultinfo, ReturnSetInfo))
- elog(ERROR, "dblink: function called in context that does not accept a set result");
-
- optstr = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(0))));
- sqlstatement = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(1))));
-
- if (fcinfo->flinfo->fn_extra == NULL)
- {
-
- conn = PQconnectdb(optstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink: connection error: %s", msg);
- }
-
- execstatement = (char *) palloc(strlen(sqlstatement) + 1);
- if (execstatement != NULL)
- {
- strcpy(execstatement, sqlstatement);
- strcat(execstatement, "\0");
- }
- else
- elog(ERROR, "dblink: insufficient memory");
-
- res = PQexec(conn, execstatement);
- if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQclear(res);
- PQfinish(conn);
- elog(ERROR, "dblink: sql error: %s", msg);
- }
- else
- {
- /*
- * got results, start fetching them
- */
- ntuples = PQntuples(res);
-
- /*
- * increment resource index
- */
- res_id_index++;
-
- results = init_dblink_results(fcinfo->flinfo->fn_mcxt);
- results->tup_num = 0;
- results->res_id_index = res_id_index;
- results->res = res;
-
- /*
- * Append node to res_id to hold pointer to results. Needed by
- * dblink_tok to access the data
- */
- append_res_ptr(results);
-
- /*
- * save pointer to results for the next function manager call
- */
- fcinfo->flinfo->fn_extra = (void *) results;
-
- /* close the connection to the database and cleanup */
- PQfinish(conn);
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprMultipleResult;
-
- PG_RETURN_INT32(res_id_index);
- }
- }
- else
- {
- /*
- * check for more results
- */
- results = fcinfo->flinfo->fn_extra;
-
- results->tup_num++;
- res_id_index = results->res_id_index;
- ntuples = PQntuples(results->res);
-
- if (results->tup_num < ntuples)
- {
- /*
- * fetch them if available
- */
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprMultipleResult;
-
- PG_RETURN_INT32(res_id_index);
- }
- else
- {
- /*
- * or if no more, clean things up
- */
- results = fcinfo->flinfo->fn_extra;
-
- remove_res_ptr(results);
- PQclear(results->res);
- pfree(results);
- fcinfo->flinfo->fn_extra = NULL;
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprEndResult;
-
- PG_RETURN_NULL();
- }
- }
- PG_RETURN_NULL();
- }
-
- /*
- * Note: dblink_tok is DEPRECATED;
- * it *will* be removed in favor of the new version on next release
- *
- * dblink_tok
- * parse dblink output string
- * return fldnum item (0 based)
- * based on provided field separator
- */
- PG_FUNCTION_INFO_V1(dblink_tok);
- Datum
- dblink_tok(PG_FUNCTION_ARGS)
- {
- dblink_results *results;
- int fldnum;
- text *result_text;
- char *result;
- int nfields = 0;
- int text_len = 0;
-
- results = get_res_ptr(PG_GETARG_INT32(0));
- if (results == NULL)
- {
- if (res_id != NIL)
- {
- freeList(res_id);
- res_id = NIL;
- res_id_index = 0;
- }
-
- elog(ERROR, "dblink_tok: function called with invalid resource id");
- }
-
- fldnum = PG_GETARG_INT32(1);
- if (fldnum < 0)
- elog(ERROR, "dblink_tok: field number < 0 not permitted");
-
- nfields = PQnfields(results->res);
- if (fldnum > (nfields - 1))
- elog(ERROR, "dblink_tok: field number %d does not exist", fldnum);
-
- if (PQgetisnull(results->res, results->tup_num, fldnum) == 1)
- PG_RETURN_NULL();
- else
- {
- text_len = PQgetlength(results->res, results->tup_num, fldnum);
-
- result = (char *) palloc(text_len + 1);
-
- if (result != NULL)
- {
- strcpy(result, PQgetvalue(results->res, results->tup_num, fldnum));
- strcat(result, "\0");
- }
- else
- elog(ERROR, "dblink: insufficient memory");
-
- result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(result)));
-
- PG_RETURN_TEXT_P(result_text);
- }
- }

/*
* dblink_get_pkey
--- 690,751 ----
{
char	   *msg;
PGresult   *res = NULL;
! 	text	   *sql_cmd_status = NULL;
TupleDesc	tupdesc = NULL;
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;
+ 	char	   *conname = NULL;
+ 	remoteConn *rcon=NULL;
+ 	bool		freeconn = true;

! if (PG_NARGS() == 2)
{
! DBLINK_GET_CONN("dblink_exec");
sql = GET_STR(PG_GETARG_TEXT_P(1));
}
! else if (PG_NARGS() == 1)
{
+ conn = persistent_conn;
sql = GET_STR(PG_GETARG_TEXT_P(0));
}
else
elog(ERROR, "dblink_exec: wrong number of arguments");

+ 	if(!conn)
+ 		DBLINK_CONN_NOT_AVAIL("dblink_exec");

res = PQexec(conn, sql);
! if (!res ||
! (PQresultStatus(res) != PGRES_COMMAND_OK &&
! PQresultStatus(res) != PGRES_TUPLES_OK))
! DBLINK_RES_ERROR("dblink_exec", "sql error");
!
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);

! /*
! * and save a copy of the command status string to return as
! * our result tuple
! */
! sql_cmd_status = GET_TEXT(PQcmdStatus(res));
}
else
! elog(ERROR, "dblink_exec: queries returning results not allowed");

PQclear(res);

/* if needed, close the connection to the database and cleanup */
! if (freeconn && fcinfo->nargs == 2)
PQfinish(conn);

! PG_RETURN_TEXT_P(sql_cmd_status);
}

/*
* dblink_get_pkey
***************
*** 927,933 ****
funcctx->user_fctx = results;
}
else
! /* fast track when no results */
SRF_RETURN_DONE(funcctx);

MemoryContextSwitchTo(oldcontext);
--- 820,826 ----
funcctx->user_fctx = results;
}
else
! 			/* fast track when no results */
SRF_RETURN_DONE(funcctx);

MemoryContextSwitchTo(oldcontext);
***************
*** 969,1005 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
- SRF_RETURN_DONE(funcctx);
- }
-
- /*
- * Note: dblink_last_oid is DEPRECATED;
- * it *will* be removed on next release
- *
- * dblink_last_oid
- * return last inserted oid
- */
- PG_FUNCTION_INFO_V1(dblink_last_oid);
- Datum
- dblink_last_oid(PG_FUNCTION_ARGS)
- {
- dblink_results *results;
-
- results = get_res_ptr(PG_GETARG_INT32(0));
- if (results == NULL)
{
! if (res_id != NIL)
! {
! freeList(res_id);
! res_id = NIL;
! res_id_index = 0;
! }
!
! elog(ERROR, "dblink_tok: function called with invalid resource id");
}
-
- PG_RETURN_OID(PQoidValue(results->res));
}

--- 862,871 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
! 		/* do when there is no more left */
! 		SRF_RETURN_DONE(funcctx);
}
}

***************
*** 1047,1053 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 913,918 ----
***************
*** 1143,1156 ****
sql = get_sql_insert(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

--- 1008,1016 ----
sql = get_sql_insert(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

***************
*** 1186,1192 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 1046,1051 ----
***************
*** 1251,1264 ****
sql = get_sql_delete(relid, pkattnums, pknumatts, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

--- 1110,1118 ----
sql = get_sql_delete(relid, pkattnums, pknumatts, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

***************
*** 1303,1309 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 1157,1162 ----
***************
*** 1399,1412 ****
sql = get_sql_update(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

/*
--- 1252,1260 ----
sql = get_sql_update(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

/*
***************
*** 1419,1428 ****
Datum
dblink_current_query(PG_FUNCTION_ARGS)
{
! text *result_text;
!
! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(debug_query_string)));
! PG_RETURN_TEXT_P(result_text);
}

--- 1267,1273 ----
Datum
dblink_current_query(PG_FUNCTION_ARGS)
{
! 	PG_RETURN_TEXT_P(GET_TEXT(debug_query_string));
}

***************
*** 1432,1460 ****

/*
-  * init_dblink_results
-  *	 - create an empty dblink_results data structure
-  */
- static dblink_results *
- init_dblink_results(MemoryContext fn_mcxt)
- {
- 	MemoryContext oldcontext;
- 	dblink_results *retval;
- 
- 	oldcontext = MemoryContextSwitchTo(fn_mcxt);
- 
- 	retval = (dblink_results *) palloc0(sizeof(dblink_results));
- 
- 	retval->tup_num = -1;
- 	retval->res_id_index = -1;
- 	retval->res = NULL;
- 
- 	MemoryContextSwitchTo(oldcontext);
- 
- 	return retval;
- }
- 
- /*
* get_pkey_attnames
*
* Get the primary key attnames for the given relation.
--- 1277,1282 ----
***************
*** 1492,1498 ****
/* we're only interested if it is the primary key */
if (index->indisprimary == TRUE)
{
! 			*numatts = index->indnatts;
if (*numatts > 0)
{
result = (char **) palloc(*numatts * sizeof(char *));
--- 1314,1323 ----
/* we're only interested if it is the primary key */
if (index->indisprimary == TRUE)
{
! 			i = 0;
! 			while (index->indkey[i++] != 0)
! 				(*numatts)++;
! 
if (*numatts > 0)
{
result = (char **) palloc(*numatts * sizeof(char *));
***************
*** 1911,1962 ****
return relid;
}

- static dblink_results *
- get_res_ptr(int32 res_id_index)
- {
- 	List	   *ptr;
- 
- 	/*
- 	 * short circuit empty list
- 	 */
- 	if (res_id == NIL)
- 		return NULL;
- 
- 	/*
- 	 * OK, should be good to go
- 	 */
- 	foreach(ptr, res_id)
- 	{
- 		dblink_results *this_res_id = (dblink_results *) lfirst(ptr);
- 
- 		if (this_res_id->res_id_index == res_id_index)
- 			return this_res_id;
- 	}
- 	return NULL;
- }
- 
- /*
-  * Add node to global List res_id
-  */
- static void
- append_res_ptr(dblink_results * results)
- {
- 	res_id = lappend(res_id, results);
- }
- 
- /*
-  * Remove node from global List
-  * using res_id_index
-  */
- static void
- remove_res_ptr(dblink_results * results)
- {
- 	res_id = lremove(results, res_id);
- 
- 	if (res_id == NIL)
- 		res_id_index = 0;
- }
- 
static TupleDesc
pgresultGetTupleDesc(PGresult *res)
{
--- 1736,1741 ----
***************
*** 2042,2045 ****
--- 1821,1912 ----
ReleaseSysCache(tp);

return result;
+ }
+ 
+ 
+ static remoteConn *
+ getConnectionByName(const char *name)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 	hentry = (remoteConnHashEnt*) hash_search(remoteConnHash,
+ 											  key, HASH_FIND, NULL);
+ 
+ 	if(hentry)
+ 		return(hentry->rcon);
+ 
+ 	return(NULL);
+ }
+ 
+ static HTAB *
+ createConnHash(void)
+ {
+ 	HASHCTL	ctl;
+ 	HTAB   *ptr;
+ 
+ 	ctl.keysize = NAMEDATALEN;
+ 	ctl.entrysize = sizeof(remoteConnHashEnt);
+ 
+ 	ptr=hash_create("Remote Con hash", NUMCONN, &ctl, HASH_ELEM);
+ 
+ 	if(!ptr)
+ 		elog(ERROR,"Can not create connections hash table. Out of memory");
+ 
+ 	return(ptr);
+ }
+ 
+ static bool
+ createNewConnection(const char *name, remoteConn *con)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	bool				found;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 	hentry = (remoteConnHashEnt *) hash_search(remoteConnHash, key,
+ 											   HASH_ENTER, &found);
+ 
+ 	if(!hentry)
+ 		elog(ERROR, "failed to create connection");
+ 
+ 	if(found)
+ 	{
+ 		elog(NOTICE, "cannot use a connection name more than once");
+ 		return false;
+ 	}
+ 
+ 	hentry->rcon = con;
+ 	strncpy(hentry->name, name, NAMEDATALEN - 1);
+ 
+ 	return true;
+ }
+ 
+ static void
+ deleteConnection(const char *name)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	bool				found;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 
+ 	hentry = (remoteConnHashEnt *) hash_search(remoteConnHash,
+ 											   key, HASH_REMOVE, &found);
+ 
+ 	if(!hentry)
+ 		elog(WARNING,"Trying to delete a connection that does not exist");
}
Index: contrib/dblink/dblink.h
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.h,v
retrieving revision 1.9
diff -c -r1.9 dblink.h
*** contrib/dblink/dblink.h	21 Oct 2002 18:57:34 -0000	1.9
--- contrib/dblink/dblink.h	15 Jun 2003 04:18:08 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
***************
*** 31,65 ****
#define DBLINK_H

/*
-  * This struct holds the results of the remote query.
-  * Use fn_extra to hold a pointer to it across calls
-  */
- typedef struct
- {
- 	/*
- 	 * last tuple number accessed
- 	 */
- 	int			tup_num;
- 
- 	/*
- 	 * resource index number for this context
- 	 */
- 	int			res_id_index;
- 
- 	/*
- 	 * the actual query results
- 	 */
- 	PGresult   *res;
- }	dblink_results;
- 
- /*
* External declarations
*/
- /* deprecated */
- extern Datum dblink(PG_FUNCTION_ARGS);
- extern Datum dblink_tok(PG_FUNCTION_ARGS);
- 
- /* supported */
extern Datum dblink_connect(PG_FUNCTION_ARGS);
extern Datum dblink_disconnect(PG_FUNCTION_ARGS);
extern Datum dblink_open(PG_FUNCTION_ARGS);
--- 34,41 ----
***************
*** 68,74 ****
extern Datum dblink_record(PG_FUNCTION_ARGS);
extern Datum dblink_exec(PG_FUNCTION_ARGS);
extern Datum dblink_get_pkey(PG_FUNCTION_ARGS);
- extern Datum dblink_last_oid(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_insert(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_delete(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_update(PG_FUNCTION_ARGS);
--- 44,49 ----
Index: contrib/dblink/dblink.sql.in
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.sql.in,v
retrieving revision 1.7
diff -c -r1.7 dblink.sql.in
*** contrib/dblink/dblink.sql.in	18 Oct 2002 18:41:19 -0000	1.7
--- contrib/dblink/dblink.sql.in	15 Jun 2003 03:59:54 -0000
***************
*** 1,50 ****
- --
- -- Uncomment the following commented lines to use original DEPRECATED functions
- --
- --CREATE OR REPLACE FUNCTION dblink (text,text)
- --RETURNS setof int
- --AS 'MODULE_PATHNAME','dblink'
- --LANGUAGE 'C' WITH (isstrict);
- --CREATE OR REPLACE FUNCTION dblink_tok (int,int)
- --RETURNS text
- --AS 'MODULE_PATHNAME','dblink_tok'
- --LANGUAGE 'C' WITH (isstrict);
- --CREATE OR REPLACE FUNCTION dblink_last_oid (int)
- --RETURNS oid
- --AS 'MODULE_PATHNAME','dblink_last_oid'
- --LANGUAGE 'C' WITH (isstrict);
- 
CREATE OR REPLACE FUNCTION dblink_connect (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_connect'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_disconnect ()
RETURNS text
AS 'MODULE_PATHNAME','dblink_disconnect'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_open (text,text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_open'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_fetch (text,int)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_fetch'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_close (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_close'
LANGUAGE 'C' WITH (isstrict);

! -- Note: if this is not a first time install of dblink, uncomment the
! -- following DROP which prepares the database for the new, non-deprecated
! -- version.
! --DROP FUNCTION dblink (text,text);

- -- Comment out the following 3 lines if the DEPRECATED functions are used.
CREATE OR REPLACE FUNCTION dblink (text,text)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_record'
--- 1,53 ----
CREATE OR REPLACE FUNCTION dblink_connect (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_connect'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_connect (text, text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_connect'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_disconnect ()
RETURNS text
AS 'MODULE_PATHNAME','dblink_disconnect'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_disconnect (text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_disconnect'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_open (text,text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_open'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_open (text,text,text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_open'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_fetch (text,int)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_fetch'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_fetch (text,text,int)
+ RETURNS setof record
+ AS 'MODULE_PATHNAME','dblink_fetch'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_close (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_close'
LANGUAGE 'C' WITH (isstrict);

! CREATE OR REPLACE FUNCTION dblink_close (text,text)
! RETURNS text
! AS 'MODULE_PATHNAME','dblink_close'
! LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink (text,text)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_record'
Index: contrib/dblink/doc/connection
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/connection,v
retrieving revision 1.1
diff -c -r1.1 connection
*** contrib/dblink/doc/connection	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/connection	15 Jun 2003 05:26:53 -0000
***************
*** 6,26 ****
Synopsis

dblink_connect(text connstr)

Inputs

connstr

standard libpq format connection string,
e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

Outputs

Returns status = "OK"

Example usage

! test=# select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
--- 6,40 ----
Synopsis

dblink_connect(text connstr)
+ dblink_connect(text connname, text connstr)

Inputs

+   connname
+     if 2 arguments are given, the first is used as a name for a persistent
+     connection
+ 
connstr

standard libpq format connection string,
e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

+     if only one argument is given, the connection is unnamed; only one unnamed
+     connection can exist at a time
+ 
Outputs

Returns status = "OK"

Example usage

! select dblink_connect('dbname=template1');
! dblink_connect
! ----------------
! OK
! (1 row)
!
! select dblink_connect('myconn','dbname=template1');
dblink_connect
----------------
OK
***************
*** 29,43 ****
==================================================================
Name

! dblink_disconnect -- Closes the persistent connection to a remote database

Synopsis

dblink_disconnect()

Inputs

! none

Outputs

--- 43,60 ----
==================================================================
Name

! dblink_disconnect -- Closes a persistent connection to a remote database

Synopsis

dblink_disconnect()
+ dblink_disconnect(text connname)

Inputs

! connname
! if an argument is given, it is used as a name for a persistent
! connection to close; otherwiase the unnamed connection is closed

Outputs

***************
*** 51,53 ****
--- 68,75 ----
OK
(1 row)

+ select dblink_disconnect('myconn');
+  dblink_disconnect
+ -------------------
+  OK
+ (1 row)
Index: contrib/dblink/doc/cursor
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/cursor,v
retrieving revision 1.1
diff -c -r1.1 cursor
*** contrib/dblink/doc/cursor	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/cursor	15 Jun 2003 05:42:15 -0000
***************
*** 6,14 ****
--- 6,19 ----
Synopsis

dblink_open(text cursorname, text sql)
+ dblink_open(text connname, text cursorname, text sql)

Inputs

+   connname
+     if three arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

a reference name for the cursor
***************
*** 52,60 ****
--- 57,70 ----
Synopsis

dblink_fetch(text cursorname, int32 howmany)
+ dblink_fetch(text connname, text cursorname, int32 howmany)

Inputs

+   connname
+     if three arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

The reference name for the cursor
***************
*** 123,131 ****
--- 133,146 ----
Synopsis

dblink_close(text cursorname)
+ dblink_close(text connname, text cursorname)

Inputs

+   connname
+     if two arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

a reference name for the cursor
***************
*** 135,141 ****
Returns status = "OK"

Note
! dblink_connect(text connstr) must be executed first.

Example usage

--- 150,157 ----
Returns status = "OK"

Note
! dblink_connect(text connstr) or dblink_connect(text connname, text connstr)
! must be executed first.

Example usage

***************
*** 157,159 ****
--- 173,192 ----
OK
(1 row)

+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select dblink_open('myconn','foo','select proname, prosrc from pg_proc');
+  dblink_open
+ -------------
+  OK
+ (1 row)
+ 
+ select dblink_close('myconn','foo');
+  dblink_close
+ --------------
+  OK
+ (1 row)
Index: contrib/dblink/doc/deprecated
===================================================================
RCS file: contrib/dblink/doc/deprecated
diff -N contrib/dblink/doc/deprecated
*** contrib/dblink/doc/deprecated	2 Sep 2002 06:32:41 -0000	1.1
--- /dev/null	1 Jan 1970 00:00:00 -0000
***************
*** 1,105 ****
- ==================================================================
- Name
- 
- *DEPRECATED* use new dblink syntax
- dblink -- Returns a resource id for a data set from a remote database
- 
- Synopsis
- 
- dblink(text connstr, text sql)
- 
- Inputs
- 
-   connstr
- 
-     standard libpq format connection srting, 
-     e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
- 
-   sql
- 
-     sql statement that you wish to execute on the remote host
-     e.g. "select * from pg_class"
- 
- Outputs
- 
-   Returns setof int (res_id)
- 
- Example usage
- 
-   select dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                ,'select f1, f2 from mytable');
- 
- ==================================================================
- 
- Name
- 
- *DEPRECATED* use new dblink syntax
- dblink_tok -- Returns individual select field results from a dblink remote query
- 
- Synopsis
- 
- dblink_tok(int res_id, int fnumber)
- 
- Inputs
- 
-   res_id
- 
-     a resource id returned by a call to dblink()
- 
-   fnumber
- 
-     the ordinal position (zero based) of the field to be returned from the dblink result set
- 
- Outputs
- 
-   Returns text
- 
- Example usage
- 
-   select dblink_tok(t1.dblink_p,0) as f1, dblink_tok(t1.dblink_p,1) as f2
-   from (select dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                      ,'select f1, f2 from mytable') as dblink_p) as t1;
- 
- 
- ==================================================================
- *DEPRECATED* use new dblink syntax
- A more convenient way to use dblink may be to create a view:
- 
-  create view myremotetable as
-  select dblink_tok(t1.dblink_p,0) as f1, dblink_tok(t1.dblink_p,1) as f2
-  from (select dblink('hostaddr=127.0.0.1 port=5432 dbname=template1 user=postgres password=postgres'
-                     ,'select proname, prosrc from pg_proc') as dblink_p) as t1;
- 
- Then you can simply write:
- 
-    select f1, f2 from myremotetable where f1 like 'bytea%';
- 
- ==================================================================
- Name
- *DEPRECATED* use new dblink_exec syntax
- dblink_last_oid -- Returns last inserted oid
- 
- Synopsis
- 
- dblink_last_oid(int res_id) RETURNS oid
- 
- Inputs
- 
-   res_id
- 
-     any resource id returned by dblink function;
- 
- Outputs
- 
-   Returns oid of last inserted tuple
- 
- Example usage
- 
- test=# select dblink_last_oid(dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                ,'insert into mytable (f1, f2) values (1,2)'));
- 
-  dblink_last_oid
- ----------------
-  16553
- (1 row)
- 
--- 0 ----
Index: contrib/dblink/doc/execute
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/execute,v
retrieving revision 1.1
diff -c -r1.1 execute
*** contrib/dblink/doc/execute	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/execute	15 Jun 2003 05:41:10 -0000
***************
*** 6,27 ****
Synopsis

dblink_exec(text connstr, text sql)
! - or -
dblink_exec(text sql)

Inputs

connstr

! standard libpq format connection string,
! e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
! If the second form is used, then the dblink_connect(text connstr) must be
! executed first.

sql

sql statement that you wish to execute on the remote host, e.g.:
-
insert into foo values(0,'a','{"a0","b0","c0"}');

Outputs
--- 6,28 ----
Synopsis

dblink_exec(text connstr, text sql)
! dblink_exec(text connname, text sql)
dblink_exec(text sql)

Inputs

+   connname
connstr
+     If two arguments are present, the first is first assumed to be a specific
+     connection name to use. If the name is not found, the argument is then
+     assumed to be a valid connection string, of standard libpq format,
+     e.g.: "hostaddr=127.0.0.1 dbname=mydb user=postgres password=mypasswd"

! If only one argument is used, then the unnamed connection is used.

sql

sql statement that you wish to execute on the remote host, e.g.:
insert into foo values(0,'a','{"a0","b0","c0"}');

Outputs
***************
*** 36,49 ****

Example usage

! test=# select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)

! test=# select dblink_exec('insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
dblink_exec
-----------------
INSERT 943366 1
(1 row)
--- 37,62 ----

Example usage

! select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)

! select dblink_exec('insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
dblink_exec
-----------------
INSERT 943366 1
+ (1 row)
+ 
+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select dblink_exec('myconn','insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
+    dblink_exec
+ ------------------
+  INSERT 6432584 1
(1 row)
Index: contrib/dblink/doc/query
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/query,v
retrieving revision 1.1
diff -c -r1.1 query
*** contrib/dblink/doc/query	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/query	15 Jun 2003 05:39:31 -0000
***************
*** 6,22 ****
Synopsis

dblink(text connstr, text sql)
! - or -
dblink(text sql)

Inputs

connstr

! standard libpq format connection string,
! e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
! If the second form is used, then the dblink_connect(text connstr) must be
! executed first.

sql

--- 6,24 ----
Synopsis

dblink(text connstr, text sql)
! dblink(text connname, text sql)
dblink(text sql)

Inputs

+   connname
connstr
+     If two arguments are present, the first is first assumed to be a specific
+     connection name to use. If the name is not found, the argument is then
+     assumed to be a valid connection string, of standard libpq format,
+     e.g.: "hostaddr=127.0.0.1 dbname=mydb user=postgres password=mypasswd"

! If only one argument is used, then the unnamed connection is used.

sql

***************
*** 29,35 ****

Example usage

! test=# select * from dblink('dbname=template1','select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
--- 31,37 ----

Example usage

! select * from dblink('dbname=template1','select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname | prosrc
------------+------------
***************
*** 47,59 ****
byteaout | byteaout
(12 rows)

! test=# select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
(1 row)

! test=# select * from dblink('select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
--- 49,61 ----
byteaout   | byteaout
(12 rows)

! select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
(1 row)

! select * from dblink('select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
***************
*** 70,75 ****
--- 72,104 ----
byteain    | byteain
byteaout   | byteaout
(12 rows)
+ 
+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select * from dblink('myconn','select proname, prosrc from pg_proc')
+  as t1(proname name, prosrc text) where proname like 'bytea%';
+   proname   |   prosrc
+ ------------+------------
+  bytearecv  | bytearecv
+  byteasend  | byteasend
+  byteale    | byteale
+  byteagt    | byteagt
+  byteage    | byteage
+  byteane    | byteane
+  byteacmp   | byteacmp
+  bytealike  | bytealike
+  byteanlike | byteanlike
+  byteacat   | byteacat
+  byteaeq    | byteaeq
+  bytealt    | bytealt
+  byteain    | byteain
+  byteaout   | byteaout
+ (14 rows)
+ 

==================================================================
A more convenient way to use dblink may be to create a view:
Index: contrib/dblink/expected/dblink.out
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/expected/dblink.out,v
retrieving revision 1.8
diff -c -r1.8 dblink.out
*** contrib/dblink/expected/dblink.out	14 May 2003 03:25:55 -0000	1.8
--- contrib/dblink/expected/dblink.out	15 Jun 2003 04:11:11 -0000
***************
*** 106,116 ****
9 | j | {a9,b9,c9}
(2 rows)

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: no connection available
-- create a persistent connection
SELECT dblink_connect('dbname=regression');
dblink_connect 
--- 106,116 ----
9 | j | {a9,b9,c9}
(2 rows)

! -- should generate "connection not available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR: dblink_record: connection not available
-- create a persistent connection
SELECT dblink_connect('dbname=regression');
dblink_connect
***************
*** 172,181 ****
OK
(1 row)

! -- should generate "cursor rmt_foo_cursor does not exist" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);
! ERROR:  dblink_fetch: cursor rmt_foo_cursor does not exist
-- close the persistent connection
SELECT dblink_disconnect();
dblink_disconnect 
--- 172,181 ----
OK
(1 row)

! -- should generate "cursor not found: rmt_foo_cursor" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);
! ERROR: dblink_fetch: cursor not found: rmt_foo_cursor
-- close the persistent connection
SELECT dblink_disconnect();
dblink_disconnect
***************
*** 183,193 ****
OK
(1 row)

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: no connection available
-- put more data into our slave table, first using arbitrary connection syntax
-- but truncate the actual return value so we can use diff to check for success
SELECT substr(dblink_exec('dbname=regression','INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
--- 183,194 ----
OK
(1 row)

! -- should generate "no connection to the server" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: sql error: no connection to the server
! 
-- put more data into our slave table, first using arbitrary connection syntax
-- but truncate the actual return value so we can use diff to check for success
SELECT substr(dblink_exec('dbname=regression','INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
***************
*** 268,270 ****
--- 269,466 ----
OK
(1 row)

+ --
+ -- tests for the new named persistent connection syntax
+ --
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ ERROR:  dblink: connection error: missing "=" after "myconn" in connection info string
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- use the named persistent connection
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- create a second named persistent connection
+ -- should error with "cannot save named connection"
+ SELECT dblink_connect('myconn','dbname=regression');
+ NOTICE:  cannot use a connection name more than once
+ ERROR:  dblink_connect: cannot save named connection
+ -- create a second named persistent connection with a new name
+ SELECT dblink_connect('myconn2','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- use the second named persistent connection
+ SELECT *
+ FROM dblink('myconn2','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- close the second named persistent connection
+ SELECT dblink_disconnect('myconn2');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- open a cursor
+ SELECT dblink_open('myconn','rmt_foo_cursor','SELECT * FROM foo');
+  dblink_open 
+ -------------
+  OK
+ (1 row)
+ 
+ -- fetch some data
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a | b |     c      
+ ---+---+------------
+  0 | a | {a0,b0,c0}
+  1 | b | {a1,b1,c1}
+  2 | c | {a2,b2,c2}
+  3 | d | {a3,b3,c3}
+ (4 rows)
+ 
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a | b |     c      
+ ---+---+------------
+  4 | e | {a4,b4,c4}
+  5 | f | {a5,b5,c5}
+  6 | g | {a6,b6,c6}
+  7 | h | {a7,b7,c7}
+ (4 rows)
+ 
+ -- this one only finds three rows left
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- close the cursor
+ SELECT dblink_close('myconn','rmt_foo_cursor');
+  dblink_close 
+ --------------
+  OK
+ (1 row)
+ 
+ -- should generate "cursor not found: rmt_foo_cursor" error
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ ERROR:  dblink_fetch: cursor not found: rmt_foo_cursor
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ ERROR:  dblink: connection error: missing "=" after "myconn" in connection info string
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- put more data into our slave table, using named persistent connection syntax
+ -- but truncate the actual return value so we can use diff to check for success
+ SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
+  substr 
+ --------
+  INSERT
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[]);
+  a  | b |       c       
+ ----+---+---------------
+   0 | a | {a0,b0,c0}
+   1 | b | {a1,b1,c1}
+   2 | c | {a2,b2,c2}
+   3 | d | {a3,b3,c3}
+   4 | e | {a4,b4,c4}
+   5 | f | {a5,b5,c5}
+   6 | g | {a6,b6,c6}
+   7 | h | {a7,b7,c7}
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+  11 | l | {a11,b11,c11}
+ (12 rows)
+ 
+ -- change some data
+ SELECT dblink_exec('myconn','UPDATE foo SET f3[2] = ''b99'' WHERE f1 = 11');
+  dblink_exec 
+ -------------
+  UPDATE 1
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+  a  | b |       c       
+ ----+---+---------------
+  11 | l | {a11,b99,c11}
+ (1 row)
+ 
+ -- delete some data
+ SELECT dblink_exec('myconn','DELETE FROM foo WHERE f1 = 11');
+  dblink_exec 
+ -------------
+  DELETE 1
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+  a | b | c 
+ ---+---+---
+ (0 rows)
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- close the named persistent connection again
+ -- should get "connection named "myconn" not found" error
+ SELECT dblink_disconnect('myconn');
+ ERROR:  dblink_disconnect: connection named "myconn" not found
Index: contrib/dblink/sql/dblink.sql
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/sql/dblink.sql,v
retrieving revision 1.8
diff -c -r1.8 dblink.sql
*** contrib/dblink/sql/dblink.sql	14 May 2003 03:25:55 -0000	1.8
--- contrib/dblink/sql/dblink.sql	15 Jun 2003 04:10:59 -0000
***************
*** 68,74 ****
FROM dblink('dbname=regression','SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
--- 68,74 ----
FROM dblink('dbname=regression','SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;

! -- should generate "connection not available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
***************
*** 98,111 ****
-- close the cursor
SELECT dblink_close('rmt_foo_cursor');

! -- should generate "cursor rmt_foo_cursor does not exist" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);

-- close the persistent connection
SELECT dblink_disconnect();

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
--- 98,111 ----
-- close the cursor
SELECT dblink_close('rmt_foo_cursor');

! -- should generate "cursor not found: rmt_foo_cursor" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);

-- close the persistent connection
SELECT dblink_disconnect();

! -- should generate "no connection to the server" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
***************
*** 143,145 ****
--- 143,240 ----

-- close the persistent connection
SELECT dblink_disconnect();
+ 
+ --
+ -- tests for the new named persistent connection syntax
+ --
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- use the named persistent connection
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a second named persistent connection
+ -- should error with "cannot save named connection"
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- create a second named persistent connection with a new name
+ SELECT dblink_connect('myconn2','dbname=regression');
+ 
+ -- use the second named persistent connection
+ SELECT *
+ FROM dblink('myconn2','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- close the second named persistent connection
+ SELECT dblink_disconnect('myconn2');
+ 
+ -- open a cursor
+ SELECT dblink_open('myconn','rmt_foo_cursor','SELECT * FROM foo');
+ 
+ -- fetch some data
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- this one only finds three rows left
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- close the cursor
+ SELECT dblink_close('myconn','rmt_foo_cursor');
+ 
+ -- should generate "cursor not found: rmt_foo_cursor" error
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- put more data into our slave table, using named persistent connection syntax
+ -- but truncate the actual return value so we can use diff to check for success
+ SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[]);
+ 
+ -- change some data
+ SELECT dblink_exec('myconn','UPDATE foo SET f3[2] = ''b99'' WHERE f1 = 11');
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+ 
+ -- delete some data
+ SELECT dblink_exec('myconn','DELETE FROM foo WHERE f1 = 11');
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+ 
+ -- close the named persistent connection again
+ -- should get "connection named "myconn" not found" error
+ SELECT dblink_disconnect('myconn');

---------------------------(end of broadcast)---------------------------
TIP 5: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faqs/FAQ.html

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Patch applied. Thanks.

---------------------------------------------------------------------------

Shridhar Daithankar wrote:
Content-Description: Mail message body

Hello,

Please apply attached patch to contrib/dblink. It adds named persistent
connections to dblink.

I have been working on this with Joe Conway and this patch is seems to work
without any problem.

Thanks Joe, for your assistance.

Bye
Shridhar

--
Anthony's Law of the Workshop: Any tool when dropped, will roll into the least
accessible corner of the workshop.Corollary: On the way to the corner, any
dropped tool will first strike your toes.

Content-Description: Text from file 'dblink.02.diff'

Index: contrib/dblink/README.dblink
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/README.dblink,v
retrieving revision 1.7
diff -c -r1.7 README.dblink
*** contrib/dblink/README.dblink	23 Nov 2002 18:59:25 -0000	1.7
--- contrib/dblink/README.dblink	15 Jun 2003 05:17:46 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
* 
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
* 
* Permission to use, copy, modify, and distribute this software and its
***************
*** 27,40 ****
*
*/

! Version 0.5 (25 August, 2002):
! Major overhaul to work with new backend "table function" capability. Removed
! dblink_strtok() and dblink_replace() functions because they are now
! available as backend functions (split() and replace() respectively).
! Tested under Linux (Red Hat 7.3) and PostgreSQL 7.3devel. This version
! is no longer backwards portable to PostgreSQL 7.2.

Release Notes:
Version 0.5
- dblink now supports use directly as a table function; this is the new
preferred usage going forward
--- 30,45 ----
*
*/

! Version 0.6 (14 June, 2003):
! Completely removed previously deprecated functions. Added ability
! to create "named" persistent connections in addition to the single global
! "unnamed" persistent connection.
! Tested under Linux (Red Hat 9) and PostgreSQL 7.4devel.

Release Notes:
+   Version 0.6
+     - functions deprecated in 0.5 have been removed
+     - added ability to create "named" persistent connections
Version 0.5
- dblink now supports use directly as a table function; this is the new
preferred usage going forward
***************
*** 87,121 ****
connection
------------
dblink_connect(text) RETURNS text
!        - opens a connection that will persist for duration of current
backend or until it is disconnected
dblink_disconnect() RETURNS text
!        - disconnects a persistent connection

cursor
------------
dblink_open(text,text) RETURNS text
! - opens a cursor using connection already opened with dblink_connect()
! that will persist for duration of current backend or until it is
! closed
dblink_fetch(text, int) RETURNS setof record
! - fetches data from an already opened cursor
dblink_close(text) RETURNS text
! - closes a cursor

query
------------
dblink(text,text) RETURNS setof record
! - returns a set of results from remote SELECT query
! (Note: comment out in dblink.sql to use deprecated version)
dblink(text) RETURNS setof record
! - returns a set of results from remote SELECT query, using connection
! already opened with dblink_connect()

execute
------------
dblink_exec(text, text) RETURNS text
!        - executes an INSERT/UPDATE/DELETE query remotely
dblink_exec(text) RETURNS text
- executes an INSERT/UPDATE/DELETE query remotely, using connection
already opened with dblink_connect()
--- 92,142 ----
connection
------------
dblink_connect(text) RETURNS text
!        - opens an unnamed connection that will persist for duration of
!          current backend or until it is disconnected
!      dblink_connect(text,text) RETURNS text
!        - opens a named connection that will persist for duration of current
backend or until it is disconnected
dblink_disconnect() RETURNS text
!        - disconnects the unnamed persistent connection
!      dblink_disconnect(text) RETURNS text
!        - disconnects a named persistent connection

cursor
------------
dblink_open(text,text) RETURNS text
! - opens a cursor using unnamed connection already opened with
! dblink_connect() that will persist for duration of current backend
! or until it is closed
! dblink_open(text,text,text) RETURNS text
! - opens a cursor using a named connection already opened with
! dblink_connect() that will persist for duration of current backend
! or until it is closed
dblink_fetch(text, int) RETURNS setof record
! - fetches data from an already opened cursor on the unnamed connection
! dblink_fetch(text, text, int) RETURNS setof record
! - fetches data from an already opened cursor on a named connection
dblink_close(text) RETURNS text
! - closes a cursor on the unnamed connection
! dblink_close(text,text) RETURNS text
! - closes a cursor on a named connection

query
------------
dblink(text,text) RETURNS setof record
! - returns a set of results from remote SELECT query; the first argument
! is either a connection string, or the name of an already opened
! persistant connection
dblink(text) RETURNS setof record
! - returns a set of results from remote SELECT query, using the unnamed
! connection already opened with dblink_connect()

execute
------------
dblink_exec(text, text) RETURNS text
! - executes an INSERT/UPDATE/DELETE query remotely; the first argument
! is either a connection string, or the name of an already opened
! persistant connection
dblink_exec(text) RETURNS text
- executes an INSERT/UPDATE/DELETE query remotely, using connection
already opened with dblink_connect()
***************
*** 135,153 ****
dblink_build_sql_update(text,int2vector,int2,_text,_text) RETURNS text
- builds an update statement using a local tuple, replacing the
selection key field values with alternate supplied values
-
- Not installed by default
- deprecated
- ------------
- dblink(text,text) RETURNS setof int
- - *DEPRECATED* returns a resource id for results from remote query
- (Note: must uncomment in dblink.sql to use)
- dblink_tok(int,int) RETURNS text
- - *DEPRECATED* extracts and returns individual field results; used
- only in conjunction with the *DEPRECATED* form of dblink
- (Note: must uncomment in dblink.sql to use)
- dblink_last_oid(int) RETURNS oid
- - *DEPRECATED* returns the last inserted oid

Documentation:

--- 156,161 ----
Index: contrib/dblink/dblink.c
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.c,v
retrieving revision 1.20
diff -c -r1.20 dblink.c
*** contrib/dblink/dblink.c	28 May 2003 16:03:55 -0000	1.20
--- contrib/dblink/dblink.c	15 Jun 2003 04:17:52 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
***************
*** 27,35 ****
*
*/
#include "postgres.h"
- 
#include "libpq-fe.h"
- 
#include "fmgr.h"
#include "funcapi.h"
#include "access/tupdesc.h"
--- 30,36 ----
***************
*** 51,63 ****
#include "utils/array.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"

#include "dblink.h"

/*
* Internal declarations
*/
! static dblink_results *init_dblink_results(MemoryContext fn_mcxt);
static char **get_pkey_attnames(Oid relid, int16 *numatts);
static char *get_sql_insert(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals, char **tgt_pkattvals);
static char *get_sql_delete(Oid relid, int16 *pkattnums, int16 pknumatts, char **tgt_pkattvals);
--- 52,78 ----
#include "utils/array.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
+ #include "utils/palloc.h"
+ #include "utils/dynahash.h"
+ #include "utils/hsearch.h"
+ #include "utils/memutils.h"

#include "dblink.h"

+ typedef struct remoteConn
+ {
+ 	PGconn *con;			/* Hold the remote connection */
+ 	bool remoteTrFlag;		/* Indicates whether or not a transaction
+ 							 * on remote database is in progress*/
+ } remoteConn;
+ 
/*
* Internal declarations
*/
! static remoteConn *getConnectionByName(const char *name);
! static HTAB *createConnHash(void);
! static bool createNewConnection(const char *name,remoteConn *con);
! static void deleteConnection(const char *name);
static char **get_pkey_attnames(Oid relid, int16 *numatts);
static char *get_sql_insert(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals, char **tgt_pkattvals);
static char *get_sql_delete(Oid relid, int16 *pkattnums, int16 pknumatts, char **tgt_pkattvals);
***************
*** 67,83 ****
static int16 get_attnum_pk_pos(int16 *pkattnums, int16 pknumatts, int16 key);
static HeapTuple get_tuple_of_interest(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals);
static Oid	get_relid_from_relname(text *relname_text);
- static dblink_results *get_res_ptr(int32 res_id_index);
- static void append_res_ptr(dblink_results * results);
- static void remove_res_ptr(dblink_results * results);
static TupleDesc pgresultGetTupleDesc(PGresult *res);
static char *generate_relation_name(Oid relid);

/* Global */
! List *res_id = NIL;
! int res_id_index = 0;
! PGconn *persistent_conn = NULL;

#define GET_TEXT(cstrp) DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(cstrp)))
#define GET_STR(textp) DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(textp)))
#define xpfree(var_) \
--- 82,113 ----
static int16 get_attnum_pk_pos(int16 *pkattnums, int16 pknumatts, int16 key);
static HeapTuple get_tuple_of_interest(Oid relid, int16 *pkattnums, int16 pknumatts, char **src_pkattvals);
static Oid	get_relid_from_relname(text *relname_text);
static TupleDesc pgresultGetTupleDesc(PGresult *res);
static char *generate_relation_name(Oid relid);

/* Global */
! List *res_id = NIL;
! int res_id_index = 0;
! PGconn *persistent_conn = NULL;
! static HTAB *remoteConnHash=NULL;
!
! /*
! Following is list that holds multiple remote connections.
! Calling convention of each dblink function changes to accept
! connection name as the first parameter. The connection list is
! much like ecpg e.g. a mapping between a name and a PGconn object.
! */
!
! typedef struct remoteConnHashEnt
! {
! char name[NAMEDATALEN];
! remoteConn *rcon;
! } remoteConnHashEnt;
!
! /* initial number of connection hashes */
! #define NUMCONN 16

+ /* general utility */
#define GET_TEXT(cstrp) DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(cstrp)))
#define GET_STR(textp) DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(textp)))
#define xpfree(var_) \
***************
*** 88,93 ****
--- 118,158 ----
var_ = NULL; \
} \
} while (0)
+ #define DBLINK_RES_ERROR(p1, p2) \
+ 	do { \
+ 			msg = pstrdup(PQerrorMessage(conn)); \
+ 			if (res) \
+ 				PQclear(res); \
+ 			elog(ERROR, "%s: %s: %s", p1, p2, msg); \
+ 	} while (0)
+ #define DBLINK_CONN_NOT_AVAIL(p1) \
+ 	do { \
+ 		if(conname) \
+ 			elog(ERROR, "%s: connection %s not available", p1, conname); \
+ 		else \
+ 			elog(ERROR, "%s: connection not available", p1); \
+ 	} while (0)
+ #define DBLINK_GET_CONN(p1) \
+ 	do { \
+ 			char *conname_or_str = GET_STR(PG_GETARG_TEXT_P(0)); \
+ 			rcon = getConnectionByName(conname_or_str); \
+ 			if(rcon) \
+ 			{ \
+ 				conn = rcon->con; \
+ 				freeconn = false; \
+ 			} \
+ 			else \
+ 			{ \
+ 				connstr = conname_or_str; \
+ 				conn = PQconnectdb(connstr); \
+ 				if (PQstatus(conn) == CONNECTION_BAD) \
+ 				{ \
+ 					msg = pstrdup(PQerrorMessage(conn)); \
+ 					PQfinish(conn); \
+ 					elog(ERROR, "%s: connection error: %s", p1, msg); \
+ 				} \
+ 			} \
+ 	} while (0)

/*
***************
*** 97,124 ****
Datum
dblink_connect(PG_FUNCTION_ARGS)
{
! char *connstr = GET_STR(PG_GETARG_TEXT_P(0));
char *msg;
- text *result_text;
MemoryContext oldcontext;

! if (persistent_conn != NULL)
! PQfinish(persistent_conn);

oldcontext = MemoryContextSwitchTo(TopMemoryContext);
! persistent_conn = PQconnectdb(connstr);
MemoryContextSwitchTo(oldcontext);

! if (PQstatus(persistent_conn) == CONNECTION_BAD)
{
! msg = pstrdup(PQerrorMessage(persistent_conn));
! PQfinish(persistent_conn);
! persistent_conn = NULL;
elog(ERROR, "dblink_connect: connection error: %s", msg);
}

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 162,213 ----
Datum
dblink_connect(PG_FUNCTION_ARGS)
{
! 	char	   *connstr = NULL;
! 	char	   *connname = NULL;
char	   *msg;
MemoryContext oldcontext;
+ 	PGconn	   *conn = NULL;
+ 	remoteConn *rcon = NULL;

! if(PG_NARGS()==2)
! {
! connstr = GET_STR(PG_GETARG_TEXT_P(1));
! connname = GET_STR(PG_GETARG_TEXT_P(0));
! }
! else if(PG_NARGS()==1)
! connstr = GET_STR(PG_GETARG_TEXT_P(0));

oldcontext = MemoryContextSwitchTo(TopMemoryContext);
!
! if(connname)
! rcon=(remoteConn *) palloc(sizeof(remoteConn));
! conn = PQconnectdb(connstr);
!
MemoryContextSwitchTo(oldcontext);

! if (PQstatus(conn) == CONNECTION_BAD)
{
! msg = pstrdup(PQerrorMessage(conn));
! PQfinish(conn);
! if(rcon)
! pfree(rcon);
elog(ERROR, "dblink_connect: connection error: %s", msg);
}

! if(connname)
! {
! rcon->con = conn;
! if(createNewConnection(connname, rcon) == false)
! {
! PQfinish(conn);
! pfree(rcon);
! elog(ERROR, "dblink_connect: cannot save named connection");
! }
! }
! else
! persistent_conn = conn;
!
! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 128,142 ****
Datum
dblink_disconnect(PG_FUNCTION_ARGS)
{
! text *result_text;

! if (persistent_conn != NULL)
! PQfinish(persistent_conn);

! persistent_conn = NULL;

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 217,253 ----
Datum
dblink_disconnect(PG_FUNCTION_ARGS)
{
! 	char	   *str = NULL;
! 	remoteConn *rcon = NULL;
! 	PGconn	   *conn = NULL;
! 
! 	if (PG_NARGS() ==1 )
! 	{
! 		str = GET_STR(PG_GETARG_TEXT_P(0));
! 		rcon = getConnectionByName(str);
! 		if (rcon)
! 			conn = rcon->con;
! 	}
! 	else
! 		conn = persistent_conn;

! if (!conn)
! {
! if (str)
! elog(ERROR,"dblink_disconnect: connection named \"%s\" not found",
! str);
! else
! elog(ERROR,"dblink_disconnect: connection not found");
! }

! PQfinish(conn);
! if (rcon)
! {
! deleteConnection(str);
! pfree(rcon);
! }

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 149,175 ****
char *msg;
PGresult *res = NULL;
PGconn *conn = NULL;
! text *result_text;
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
! char *sql = GET_STR(PG_GETARG_TEXT_P(1));
StringInfo str = makeStringInfo();

! if (persistent_conn != NULL)
conn = persistent_conn;
! else
! elog(ERROR, "dblink_open: no connection available");

res = PQexec(conn, "BEGIN");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(conn);
! persistent_conn = NULL;

- elog(ERROR, "dblink_open: begin error: %s", msg);
- }
PQclear(res);

appendStringInfo(str, "DECLARE %s CURSOR FOR %s", curname, sql);
--- 260,294 ----
char	   *msg;
PGresult   *res = NULL;
PGconn	   *conn = NULL;
! 	char	   *curname = NULL;
! 	char	   *sql = NULL;
! 	char	   *conname = NULL;
StringInfo	str = makeStringInfo();
+ 	remoteConn *rcon = NULL;

! if(PG_NARGS() == 2)
! {
! curname = GET_STR(PG_GETARG_TEXT_P(0));
! sql = GET_STR(PG_GETARG_TEXT_P(1));
conn = persistent_conn;
! }
! else if(PG_NARGS() == 3)
! {
! conname = GET_STR(PG_GETARG_TEXT_P(0));
! curname = GET_STR(PG_GETARG_TEXT_P(1));
! sql = GET_STR(PG_GETARG_TEXT_P(2));
! rcon = getConnectionByName(conname);
! if (rcon)
! conn = rcon->con;
! }
!
! if (!conn)
! DBLINK_CONN_NOT_AVAIL("dblink_open");

res = PQexec(conn, "BEGIN");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_open", "begin error");

PQclear(res);

appendStringInfo(str, "DECLARE %s CURSOR FOR %s", curname, sql);
***************
*** 177,195 ****
if (!res ||
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
! {
! msg = pstrdup(PQerrorMessage(conn));
!
! PQclear(res);

! PQfinish(conn);
! persistent_conn = NULL;
!
! elog(ERROR, "dblink: sql error: %s", msg);
! }

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 296,306 ----
if (!res ||
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
! 		DBLINK_RES_ERROR("dblink_open", "sql error");

! PQclear(res);

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 201,249 ****
{
PGconn *conn = NULL;
PGresult *res = NULL;
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
StringInfo str = makeStringInfo();
- text *result_text;
char *msg;

! if (persistent_conn != NULL)
conn = persistent_conn;
! else
! elog(ERROR, "dblink_close: no connection available");

appendStringInfo(str, "CLOSE %s", curname);

/* close the cursor */
res = PQexec(conn, str->data);
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(persistent_conn);
! persistent_conn = NULL;
!
! elog(ERROR, "dblink_close: sql error: %s", msg);
! }

PQclear(res);

/* commit the transaction */
res = PQexec(conn, "COMMIT");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! {
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
!
! PQfinish(persistent_conn);
! persistent_conn = NULL;

- elog(ERROR, "dblink_close: commit error: %s", msg);
- }
PQclear(res);

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum("OK")));
! PG_RETURN_TEXT_P(result_text);
}

/*
--- 312,357 ----
{
PGconn	   *conn = NULL;
PGresult   *res = NULL;
! 	char	   *curname = NULL;
! 	char	   *conname = NULL;
StringInfo	str = makeStringInfo();
char	   *msg;
+ 	remoteConn *rcon = NULL;

! if (PG_NARGS() == 1)
! {
! curname = GET_STR(PG_GETARG_TEXT_P(0));
conn = persistent_conn;
! }
! else if (PG_NARGS()==2)
! {
! conname = GET_STR(PG_GETARG_TEXT_P(0));
! curname = GET_STR(PG_GETARG_TEXT_P(1));
! rcon = getConnectionByName(conname);
! if(rcon)
! conn = rcon->con;
! }
!
! if (!conn)
! DBLINK_CONN_NOT_AVAIL("dblink_close");

appendStringInfo(str, "CLOSE %s", curname);

/* close the cursor */
res = PQexec(conn, str->data);
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_close", "sql error");

PQclear(res);

/* commit the transaction */
res = PQexec(conn, "COMMIT");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
! DBLINK_RES_ERROR("dblink_close", "commit error");

PQclear(res);

! PG_RETURN_TEXT_P(GET_TEXT("OK"));
}

/*
***************
*** 262,267 ****
--- 370,377 ----
char	   *msg;
PGresult   *res = NULL;
MemoryContext oldcontext;
+ 	char	   *conname = NULL;
+ 	remoteConn *rcon=NULL;

/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
***************
*** 271,278 ****
Oid funcid = fcinfo->flinfo->fn_oid;
PGconn *conn = NULL;
StringInfo str = makeStringInfo();
! char *curname = GET_STR(PG_GETARG_TEXT_P(0));
! int howmany = PG_GETARG_INT32(1);

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
--- 381,408 ----
Oid			funcid = fcinfo->flinfo->fn_oid;
PGconn	   *conn = NULL;
StringInfo	str = makeStringInfo();
! 		char	   *curname = NULL;
! 		int			howmany = 0;
! 
! 		if (PG_NARGS() == 3)
! 		{
! 			conname = GET_STR(PG_GETARG_TEXT_P(0));
! 			curname = GET_STR(PG_GETARG_TEXT_P(1));
! 			howmany = PG_GETARG_INT32(2);
! 
! 			rcon = getConnectionByName(conname);
! 			if(rcon)
! 				conn = rcon->con;
! 		}
! 		else if (PG_NARGS() == 2)
! 		{
! 			curname = GET_STR(PG_GETARG_TEXT_P(0));
! 			howmany = PG_GETARG_INT32(1);
! 			conn = persistent_conn;
! 		}
! 
! 		if(!conn)
! 			DBLINK_CONN_NOT_AVAIL("dblink_fetch");

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
***************
*** 283,293 ****
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink_fetch: no connection available");
-
appendStringInfo(str, "FETCH %d FROM %s", howmany, curname);

res = PQexec(conn, str->data);
--- 413,418 ----
***************
*** 295,313 ****
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
{
! 			msg = pstrdup(PQerrorMessage(conn));
! 			PQclear(res);
! 
! 			PQfinish(persistent_conn);
! 			persistent_conn = NULL;
! 
! 			elog(ERROR, "dblink_fetch: sql error: %s", msg);
}
else if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
/* cursor does not exist - closed already or bad name */
PQclear(res);
! 			elog(ERROR, "dblink_fetch: cursor %s does not exist", curname);
}

funcctx->max_calls = PQntuples(res);
--- 420,432 ----
(PQresultStatus(res) != PGRES_COMMAND_OK &&
PQresultStatus(res) != PGRES_TUPLES_OK))
{
! 			DBLINK_RES_ERROR("dblink_fetch", "sql error");
}
else if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
/* cursor does not exist - closed already or bad name */
PQclear(res);
! 			elog(ERROR, "dblink_fetch: cursor not found: %s", curname);
}

funcctx->max_calls = PQntuples(res);
***************
*** 382,389 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
{
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
--- 501,508 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
+ 		/* do when there is no more left */
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
***************
*** 407,412 ****
--- 526,532 ----
bool		is_sql_cmd = false;
char	   *sql_cmd_status = NULL;
MemoryContext oldcontext;
+ 	bool		freeconn = true;

/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
***************
*** 417,422 ****
--- 537,544 ----
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;
+ 		char	   *conname = NULL;
+ 		remoteConn *rcon=NULL;

/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
***************
*** 427,496 ****
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

! if (fcinfo->nargs == 2)
{
! connstr = GET_STR(PG_GETARG_TEXT_P(0));
sql = GET_STR(PG_GETARG_TEXT_P(1));
-
- conn = PQconnectdb(connstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink: connection error: %s", msg);
- }
}
! else if (fcinfo->nargs == 1)
{
sql = GET_STR(PG_GETARG_TEXT_P(0));
-
- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink: no connection available");
}
else
elog(ERROR, "dblink: wrong number of arguments");

res = PQexec(conn, sql);
if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
{
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
! PQfinish(conn);
! if (fcinfo->nargs == 1)
! persistent_conn = NULL;

! elog(ERROR, "dblink: sql error: %s", msg);
}
else
! {
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
! {
! is_sql_cmd = true;

! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);
!
! /*
! * and save a copy of the command status string to return
! * as our result tuple
! */
! sql_cmd_status = PQcmdStatus(res);
! funcctx->max_calls = 1;
! }
! else
! funcctx->max_calls = PQntuples(res);
!
! /* got results, keep track of them */
! funcctx->user_fctx = res;

! /* if needed, close the connection to the database and cleanup */
! if (fcinfo->nargs == 2)
! PQfinish(conn);
! }

/* fast track when no results */
if (funcctx->max_calls < 1)
--- 549,599 ----
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

! if (PG_NARGS() == 2)
{
! DBLINK_GET_CONN("dblink");
sql = GET_STR(PG_GETARG_TEXT_P(1));
}
! else if (PG_NARGS() == 1)
{
+ conn = persistent_conn;
sql = GET_STR(PG_GETARG_TEXT_P(0));
}
else
elog(ERROR, "dblink: wrong number of arguments");

+ 		if(!conn)
+ 			DBLINK_CONN_NOT_AVAIL("dblink_record");
+ 
res = PQexec(conn, sql);
if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
+ 			DBLINK_RES_ERROR("dblink", "sql error");
+ 
+ 		if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
! 			is_sql_cmd = true;
! 
! 			/* need a tuple descriptor representing one TEXT column */
! 			tupdesc = CreateTemplateTupleDesc(1, false);
! 			TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! 							   TEXTOID, -1, 0, false);

! /*
! * and save a copy of the command status string to return
! * as our result tuple
! */
! sql_cmd_status = PQcmdStatus(res);
! funcctx->max_calls = 1;
}
else
! funcctx->max_calls = PQntuples(res);

! /* got results, keep track of them */
! funcctx->user_fctx = res;

! /* if needed, close the connection to the database and cleanup */
! if (freeconn && PG_NARGS() == 2)
! PQfinish(conn);

/* fast track when no results */
if (funcctx->max_calls < 1)
***************
*** 571,578 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
{
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
--- 674,681 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
+ 		/* do when there is no more left */
PQclear(res);
SRF_RETURN_DONE(funcctx);
}
***************
*** 587,858 ****
{
char	   *msg;
PGresult   *res = NULL;
! 	char	   *sql_cmd_status = NULL;
TupleDesc	tupdesc = NULL;
- 	text	   *result_text;
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;

! if (fcinfo->nargs == 2)
{
! connstr = GET_STR(PG_GETARG_TEXT_P(0));
sql = GET_STR(PG_GETARG_TEXT_P(1));
-
- conn = PQconnectdb(connstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink_exec: connection error: %s", msg);
- }
}
! else if (fcinfo->nargs == 1)
{
sql = GET_STR(PG_GETARG_TEXT_P(0));
-
- if (persistent_conn != NULL)
- conn = persistent_conn;
- else
- elog(ERROR, "dblink_exec: no connection available");
}
else
elog(ERROR, "dblink_exec: wrong number of arguments");

res = PQexec(conn, sql);
! if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
{
! msg = pstrdup(PQerrorMessage(conn));
! PQclear(res);
! PQfinish(conn);
! if (fcinfo->nargs == 1)
! persistent_conn = NULL;

! elog(ERROR, "dblink_exec: sql error: %s", msg);
}
else
! {
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
! {
! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);

- /*
- * and save a copy of the command status string to return as
- * our result tuple
- */
- sql_cmd_status = PQcmdStatus(res);
- }
- else
- elog(ERROR, "dblink_exec: queries returning results not allowed");
- }
PQclear(res);

/* if needed, close the connection to the database and cleanup */
! if (fcinfo->nargs == 2)
PQfinish(conn);

! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql_cmd_status)));
! PG_RETURN_TEXT_P(result_text);
}

- /*
- * Note: this original version of dblink is DEPRECATED;
- * it *will* be removed in favor of the new version on next release
- */
- PG_FUNCTION_INFO_V1(dblink);
- Datum
- dblink(PG_FUNCTION_ARGS)
- {
- PGconn *conn = NULL;
- PGresult *res = NULL;
- dblink_results *results;
- char *optstr;
- char *sqlstatement;
- char *execstatement;
- char *msg;
- int ntuples = 0;
- ReturnSetInfo *rsi;
-
- if (fcinfo->resultinfo == NULL || !IsA(fcinfo->resultinfo, ReturnSetInfo))
- elog(ERROR, "dblink: function called in context that does not accept a set result");
-
- optstr = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(0))));
- sqlstatement = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(1))));
-
- if (fcinfo->flinfo->fn_extra == NULL)
- {
-
- conn = PQconnectdb(optstr);
- if (PQstatus(conn) == CONNECTION_BAD)
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQfinish(conn);
- elog(ERROR, "dblink: connection error: %s", msg);
- }
-
- execstatement = (char *) palloc(strlen(sqlstatement) + 1);
- if (execstatement != NULL)
- {
- strcpy(execstatement, sqlstatement);
- strcat(execstatement, "\0");
- }
- else
- elog(ERROR, "dblink: insufficient memory");
-
- res = PQexec(conn, execstatement);
- if (!res || (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK))
- {
- msg = pstrdup(PQerrorMessage(conn));
- PQclear(res);
- PQfinish(conn);
- elog(ERROR, "dblink: sql error: %s", msg);
- }
- else
- {
- /*
- * got results, start fetching them
- */
- ntuples = PQntuples(res);
-
- /*
- * increment resource index
- */
- res_id_index++;
-
- results = init_dblink_results(fcinfo->flinfo->fn_mcxt);
- results->tup_num = 0;
- results->res_id_index = res_id_index;
- results->res = res;
-
- /*
- * Append node to res_id to hold pointer to results. Needed by
- * dblink_tok to access the data
- */
- append_res_ptr(results);
-
- /*
- * save pointer to results for the next function manager call
- */
- fcinfo->flinfo->fn_extra = (void *) results;
-
- /* close the connection to the database and cleanup */
- PQfinish(conn);
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprMultipleResult;
-
- PG_RETURN_INT32(res_id_index);
- }
- }
- else
- {
- /*
- * check for more results
- */
- results = fcinfo->flinfo->fn_extra;
-
- results->tup_num++;
- res_id_index = results->res_id_index;
- ntuples = PQntuples(results->res);
-
- if (results->tup_num < ntuples)
- {
- /*
- * fetch them if available
- */
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprMultipleResult;
-
- PG_RETURN_INT32(res_id_index);
- }
- else
- {
- /*
- * or if no more, clean things up
- */
- results = fcinfo->flinfo->fn_extra;
-
- remove_res_ptr(results);
- PQclear(results->res);
- pfree(results);
- fcinfo->flinfo->fn_extra = NULL;
-
- rsi = (ReturnSetInfo *) fcinfo->resultinfo;
- rsi->isDone = ExprEndResult;
-
- PG_RETURN_NULL();
- }
- }
- PG_RETURN_NULL();
- }
-
- /*
- * Note: dblink_tok is DEPRECATED;
- * it *will* be removed in favor of the new version on next release
- *
- * dblink_tok
- * parse dblink output string
- * return fldnum item (0 based)
- * based on provided field separator
- */
- PG_FUNCTION_INFO_V1(dblink_tok);
- Datum
- dblink_tok(PG_FUNCTION_ARGS)
- {
- dblink_results *results;
- int fldnum;
- text *result_text;
- char *result;
- int nfields = 0;
- int text_len = 0;
-
- results = get_res_ptr(PG_GETARG_INT32(0));
- if (results == NULL)
- {
- if (res_id != NIL)
- {
- freeList(res_id);
- res_id = NIL;
- res_id_index = 0;
- }
-
- elog(ERROR, "dblink_tok: function called with invalid resource id");
- }
-
- fldnum = PG_GETARG_INT32(1);
- if (fldnum < 0)
- elog(ERROR, "dblink_tok: field number < 0 not permitted");
-
- nfields = PQnfields(results->res);
- if (fldnum > (nfields - 1))
- elog(ERROR, "dblink_tok: field number %d does not exist", fldnum);
-
- if (PQgetisnull(results->res, results->tup_num, fldnum) == 1)
- PG_RETURN_NULL();
- else
- {
- text_len = PQgetlength(results->res, results->tup_num, fldnum);
-
- result = (char *) palloc(text_len + 1);
-
- if (result != NULL)
- {
- strcpy(result, PQgetvalue(results->res, results->tup_num, fldnum));
- strcat(result, "\0");
- }
- else
- elog(ERROR, "dblink: insufficient memory");
-
- result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(result)));
-
- PG_RETURN_TEXT_P(result_text);
- }
- }

/*
* dblink_get_pkey
--- 690,751 ----
{
char	   *msg;
PGresult   *res = NULL;
! 	text	   *sql_cmd_status = NULL;
TupleDesc	tupdesc = NULL;
PGconn	   *conn = NULL;
char	   *connstr = NULL;
char	   *sql = NULL;
+ 	char	   *conname = NULL;
+ 	remoteConn *rcon=NULL;
+ 	bool		freeconn = true;

! if (PG_NARGS() == 2)
{
! DBLINK_GET_CONN("dblink_exec");
sql = GET_STR(PG_GETARG_TEXT_P(1));
}
! else if (PG_NARGS() == 1)
{
+ conn = persistent_conn;
sql = GET_STR(PG_GETARG_TEXT_P(0));
}
else
elog(ERROR, "dblink_exec: wrong number of arguments");

+ 	if(!conn)
+ 		DBLINK_CONN_NOT_AVAIL("dblink_exec");

res = PQexec(conn, sql);
! if (!res ||
! (PQresultStatus(res) != PGRES_COMMAND_OK &&
! PQresultStatus(res) != PGRES_TUPLES_OK))
! DBLINK_RES_ERROR("dblink_exec", "sql error");
!
! if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
! /* need a tuple descriptor representing one TEXT column */
! tupdesc = CreateTemplateTupleDesc(1, false);
! TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
! TEXTOID, -1, 0, false);

! /*
! * and save a copy of the command status string to return as
! * our result tuple
! */
! sql_cmd_status = GET_TEXT(PQcmdStatus(res));
}
else
! elog(ERROR, "dblink_exec: queries returning results not allowed");

PQclear(res);

/* if needed, close the connection to the database and cleanup */
! if (freeconn && fcinfo->nargs == 2)
PQfinish(conn);

! PG_RETURN_TEXT_P(sql_cmd_status);
}

/*
* dblink_get_pkey
***************
*** 927,933 ****
funcctx->user_fctx = results;
}
else
! /* fast track when no results */
SRF_RETURN_DONE(funcctx);

MemoryContextSwitchTo(oldcontext);
--- 820,826 ----
funcctx->user_fctx = results;
}
else
! 			/* fast track when no results */
SRF_RETURN_DONE(funcctx);

MemoryContextSwitchTo(oldcontext);
***************
*** 969,1005 ****
SRF_RETURN_NEXT(funcctx, result);
}
else
- /* do when there is no more left */
- SRF_RETURN_DONE(funcctx);
- }
-
- /*
- * Note: dblink_last_oid is DEPRECATED;
- * it *will* be removed on next release
- *
- * dblink_last_oid
- * return last inserted oid
- */
- PG_FUNCTION_INFO_V1(dblink_last_oid);
- Datum
- dblink_last_oid(PG_FUNCTION_ARGS)
- {
- dblink_results *results;
-
- results = get_res_ptr(PG_GETARG_INT32(0));
- if (results == NULL)
{
! if (res_id != NIL)
! {
! freeList(res_id);
! res_id = NIL;
! res_id_index = 0;
! }
!
! elog(ERROR, "dblink_tok: function called with invalid resource id");
}
-
- PG_RETURN_OID(PQoidValue(results->res));
}

--- 862,871 ----
SRF_RETURN_NEXT(funcctx, result);
}
else
{
! 		/* do when there is no more left */
! 		SRF_RETURN_DONE(funcctx);
}
}

***************
*** 1047,1053 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 913,918 ----
***************
*** 1143,1156 ****
sql = get_sql_insert(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

--- 1008,1016 ----
sql = get_sql_insert(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

***************
*** 1186,1192 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 1046,1051 ----
***************
*** 1251,1264 ****
sql = get_sql_delete(relid, pkattnums, pknumatts, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

--- 1110,1118 ----
sql = get_sql_delete(relid, pkattnums, pknumatts, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

***************
*** 1303,1309 ****
int			i;
char	   *ptr;
char	   *sql;
- 	text	   *sql_text;
int16		typlen;
bool		typbyval;
char		typalign;
--- 1157,1162 ----
***************
*** 1399,1412 ****
sql = get_sql_update(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
- * Make it into TEXT for return to the client
- */
- sql_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(sql)));
-
- /*
* And send it
*/
! PG_RETURN_TEXT_P(sql_text);
}

/*
--- 1252,1260 ----
sql = get_sql_update(relid, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);

/*
* And send it
*/
! PG_RETURN_TEXT_P(GET_TEXT(sql));
}

/*
***************
*** 1419,1428 ****
Datum
dblink_current_query(PG_FUNCTION_ARGS)
{
! text *result_text;
!
! result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(debug_query_string)));
! PG_RETURN_TEXT_P(result_text);
}

--- 1267,1273 ----
Datum
dblink_current_query(PG_FUNCTION_ARGS)
{
! 	PG_RETURN_TEXT_P(GET_TEXT(debug_query_string));
}

***************
*** 1432,1460 ****

/*
-  * init_dblink_results
-  *	 - create an empty dblink_results data structure
-  */
- static dblink_results *
- init_dblink_results(MemoryContext fn_mcxt)
- {
- 	MemoryContext oldcontext;
- 	dblink_results *retval;
- 
- 	oldcontext = MemoryContextSwitchTo(fn_mcxt);
- 
- 	retval = (dblink_results *) palloc0(sizeof(dblink_results));
- 
- 	retval->tup_num = -1;
- 	retval->res_id_index = -1;
- 	retval->res = NULL;
- 
- 	MemoryContextSwitchTo(oldcontext);
- 
- 	return retval;
- }
- 
- /*
* get_pkey_attnames
*
* Get the primary key attnames for the given relation.
--- 1277,1282 ----
***************
*** 1492,1498 ****
/* we're only interested if it is the primary key */
if (index->indisprimary == TRUE)
{
! 			*numatts = index->indnatts;
if (*numatts > 0)
{
result = (char **) palloc(*numatts * sizeof(char *));
--- 1314,1323 ----
/* we're only interested if it is the primary key */
if (index->indisprimary == TRUE)
{
! 			i = 0;
! 			while (index->indkey[i++] != 0)
! 				(*numatts)++;
! 
if (*numatts > 0)
{
result = (char **) palloc(*numatts * sizeof(char *));
***************
*** 1911,1962 ****
return relid;
}

- static dblink_results *
- get_res_ptr(int32 res_id_index)
- {
- 	List	   *ptr;
- 
- 	/*
- 	 * short circuit empty list
- 	 */
- 	if (res_id == NIL)
- 		return NULL;
- 
- 	/*
- 	 * OK, should be good to go
- 	 */
- 	foreach(ptr, res_id)
- 	{
- 		dblink_results *this_res_id = (dblink_results *) lfirst(ptr);
- 
- 		if (this_res_id->res_id_index == res_id_index)
- 			return this_res_id;
- 	}
- 	return NULL;
- }
- 
- /*
-  * Add node to global List res_id
-  */
- static void
- append_res_ptr(dblink_results * results)
- {
- 	res_id = lappend(res_id, results);
- }
- 
- /*
-  * Remove node from global List
-  * using res_id_index
-  */
- static void
- remove_res_ptr(dblink_results * results)
- {
- 	res_id = lremove(results, res_id);
- 
- 	if (res_id == NIL)
- 		res_id_index = 0;
- }
- 
static TupleDesc
pgresultGetTupleDesc(PGresult *res)
{
--- 1736,1741 ----
***************
*** 2042,2045 ****
--- 1821,1912 ----
ReleaseSysCache(tp);

return result;
+ }
+ 
+ 
+ static remoteConn *
+ getConnectionByName(const char *name)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 	hentry = (remoteConnHashEnt*) hash_search(remoteConnHash,
+ 											  key, HASH_FIND, NULL);
+ 
+ 	if(hentry)
+ 		return(hentry->rcon);
+ 
+ 	return(NULL);
+ }
+ 
+ static HTAB *
+ createConnHash(void)
+ {
+ 	HASHCTL	ctl;
+ 	HTAB   *ptr;
+ 
+ 	ctl.keysize = NAMEDATALEN;
+ 	ctl.entrysize = sizeof(remoteConnHashEnt);
+ 
+ 	ptr=hash_create("Remote Con hash", NUMCONN, &ctl, HASH_ELEM);
+ 
+ 	if(!ptr)
+ 		elog(ERROR,"Can not create connections hash table. Out of memory");
+ 
+ 	return(ptr);
+ }
+ 
+ static bool
+ createNewConnection(const char *name, remoteConn *con)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	bool				found;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 	hentry = (remoteConnHashEnt *) hash_search(remoteConnHash, key,
+ 											   HASH_ENTER, &found);
+ 
+ 	if(!hentry)
+ 		elog(ERROR, "failed to create connection");
+ 
+ 	if(found)
+ 	{
+ 		elog(NOTICE, "cannot use a connection name more than once");
+ 		return false;
+ 	}
+ 
+ 	hentry->rcon = con;
+ 	strncpy(hentry->name, name, NAMEDATALEN - 1);
+ 
+ 	return true;
+ }
+ 
+ static void
+ deleteConnection(const char *name)
+ {
+ 	remoteConnHashEnt  *hentry;
+ 	bool				found;
+ 	char				key[NAMEDATALEN];
+ 
+ 	if(!remoteConnHash)
+ 		remoteConnHash=createConnHash();
+ 
+ 	MemSet(key, 0, NAMEDATALEN);
+ 	snprintf(key, NAMEDATALEN - 1, "%s", name);
+ 
+ 	hentry = (remoteConnHashEnt *) hash_search(remoteConnHash,
+ 											   key, HASH_REMOVE, &found);
+ 
+ 	if(!hentry)
+ 		elog(WARNING,"Trying to delete a connection that does not exist");
}
Index: contrib/dblink/dblink.h
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.h,v
retrieving revision 1.9
diff -c -r1.9 dblink.h
*** contrib/dblink/dblink.h	21 Oct 2002 18:57:34 -0000	1.9
--- contrib/dblink/dblink.h	15 Jun 2003 04:18:08 -0000
***************
*** 4,11 ****
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
*
!  * Copyright (c) 2001, 2002 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
--- 4,14 ----
* Functions returning results from a remote database
*
* Joe Conway <mail@joeconway.com>
+  * And contributors:
+  * Darko Prenosil <Darko.Prenosil@finteh.hr>
+  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
*
!  * Copyright (c) 2001, 2002, 2003 by PostgreSQL Global Development Group
* ALL RIGHTS RESERVED;
*
* Permission to use, copy, modify, and distribute this software and its
***************
*** 31,65 ****
#define DBLINK_H

/*
-  * This struct holds the results of the remote query.
-  * Use fn_extra to hold a pointer to it across calls
-  */
- typedef struct
- {
- 	/*
- 	 * last tuple number accessed
- 	 */
- 	int			tup_num;
- 
- 	/*
- 	 * resource index number for this context
- 	 */
- 	int			res_id_index;
- 
- 	/*
- 	 * the actual query results
- 	 */
- 	PGresult   *res;
- }	dblink_results;
- 
- /*
* External declarations
*/
- /* deprecated */
- extern Datum dblink(PG_FUNCTION_ARGS);
- extern Datum dblink_tok(PG_FUNCTION_ARGS);
- 
- /* supported */
extern Datum dblink_connect(PG_FUNCTION_ARGS);
extern Datum dblink_disconnect(PG_FUNCTION_ARGS);
extern Datum dblink_open(PG_FUNCTION_ARGS);
--- 34,41 ----
***************
*** 68,74 ****
extern Datum dblink_record(PG_FUNCTION_ARGS);
extern Datum dblink_exec(PG_FUNCTION_ARGS);
extern Datum dblink_get_pkey(PG_FUNCTION_ARGS);
- extern Datum dblink_last_oid(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_insert(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_delete(PG_FUNCTION_ARGS);
extern Datum dblink_build_sql_update(PG_FUNCTION_ARGS);
--- 44,49 ----
Index: contrib/dblink/dblink.sql.in
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/dblink.sql.in,v
retrieving revision 1.7
diff -c -r1.7 dblink.sql.in
*** contrib/dblink/dblink.sql.in	18 Oct 2002 18:41:19 -0000	1.7
--- contrib/dblink/dblink.sql.in	15 Jun 2003 03:59:54 -0000
***************
*** 1,50 ****
- --
- -- Uncomment the following commented lines to use original DEPRECATED functions
- --
- --CREATE OR REPLACE FUNCTION dblink (text,text)
- --RETURNS setof int
- --AS 'MODULE_PATHNAME','dblink'
- --LANGUAGE 'C' WITH (isstrict);
- --CREATE OR REPLACE FUNCTION dblink_tok (int,int)
- --RETURNS text
- --AS 'MODULE_PATHNAME','dblink_tok'
- --LANGUAGE 'C' WITH (isstrict);
- --CREATE OR REPLACE FUNCTION dblink_last_oid (int)
- --RETURNS oid
- --AS 'MODULE_PATHNAME','dblink_last_oid'
- --LANGUAGE 'C' WITH (isstrict);
- 
CREATE OR REPLACE FUNCTION dblink_connect (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_connect'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_disconnect ()
RETURNS text
AS 'MODULE_PATHNAME','dblink_disconnect'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_open (text,text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_open'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_fetch (text,int)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_fetch'
LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink_close (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_close'
LANGUAGE 'C' WITH (isstrict);

! -- Note: if this is not a first time install of dblink, uncomment the
! -- following DROP which prepares the database for the new, non-deprecated
! -- version.
! --DROP FUNCTION dblink (text,text);

- -- Comment out the following 3 lines if the DEPRECATED functions are used.
CREATE OR REPLACE FUNCTION dblink (text,text)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_record'
--- 1,53 ----
CREATE OR REPLACE FUNCTION dblink_connect (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_connect'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_connect (text, text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_connect'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_disconnect ()
RETURNS text
AS 'MODULE_PATHNAME','dblink_disconnect'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_disconnect (text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_disconnect'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_open (text,text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_open'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_open (text,text,text)
+ RETURNS text
+ AS 'MODULE_PATHNAME','dblink_open'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_fetch (text,int)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_fetch'
LANGUAGE 'C' WITH (isstrict);

+ CREATE OR REPLACE FUNCTION dblink_fetch (text,text,int)
+ RETURNS setof record
+ AS 'MODULE_PATHNAME','dblink_fetch'
+ LANGUAGE 'C' WITH (isstrict);
+ 
CREATE OR REPLACE FUNCTION dblink_close (text)
RETURNS text
AS 'MODULE_PATHNAME','dblink_close'
LANGUAGE 'C' WITH (isstrict);

! CREATE OR REPLACE FUNCTION dblink_close (text,text)
! RETURNS text
! AS 'MODULE_PATHNAME','dblink_close'
! LANGUAGE 'C' WITH (isstrict);

CREATE OR REPLACE FUNCTION dblink (text,text)
RETURNS setof record
AS 'MODULE_PATHNAME','dblink_record'
Index: contrib/dblink/doc/connection
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/connection,v
retrieving revision 1.1
diff -c -r1.1 connection
*** contrib/dblink/doc/connection	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/connection	15 Jun 2003 05:26:53 -0000
***************
*** 6,26 ****
Synopsis

dblink_connect(text connstr)

Inputs

connstr

standard libpq format connection string,
e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

Outputs

Returns status = "OK"

Example usage

! test=# select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
--- 6,40 ----
Synopsis

dblink_connect(text connstr)
+ dblink_connect(text connname, text connstr)

Inputs

+   connname
+     if 2 arguments are given, the first is used as a name for a persistent
+     connection
+ 
connstr

standard libpq format connection string,
e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

+     if only one argument is given, the connection is unnamed; only one unnamed
+     connection can exist at a time
+ 
Outputs

Returns status = "OK"

Example usage

! select dblink_connect('dbname=template1');
! dblink_connect
! ----------------
! OK
! (1 row)
!
! select dblink_connect('myconn','dbname=template1');
dblink_connect
----------------
OK
***************
*** 29,43 ****
==================================================================
Name

! dblink_disconnect -- Closes the persistent connection to a remote database

Synopsis

dblink_disconnect()

Inputs

! none

Outputs

--- 43,60 ----
==================================================================
Name

! dblink_disconnect -- Closes a persistent connection to a remote database

Synopsis

dblink_disconnect()
+ dblink_disconnect(text connname)

Inputs

! connname
! if an argument is given, it is used as a name for a persistent
! connection to close; otherwiase the unnamed connection is closed

Outputs

***************
*** 51,53 ****
--- 68,75 ----
OK
(1 row)

+ select dblink_disconnect('myconn');
+  dblink_disconnect
+ -------------------
+  OK
+ (1 row)
Index: contrib/dblink/doc/cursor
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/cursor,v
retrieving revision 1.1
diff -c -r1.1 cursor
*** contrib/dblink/doc/cursor	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/cursor	15 Jun 2003 05:42:15 -0000
***************
*** 6,14 ****
--- 6,19 ----
Synopsis

dblink_open(text cursorname, text sql)
+ dblink_open(text connname, text cursorname, text sql)

Inputs

+   connname
+     if three arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

a reference name for the cursor
***************
*** 52,60 ****
--- 57,70 ----
Synopsis

dblink_fetch(text cursorname, int32 howmany)
+ dblink_fetch(text connname, text cursorname, int32 howmany)

Inputs

+   connname
+     if three arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

The reference name for the cursor
***************
*** 123,131 ****
--- 133,146 ----
Synopsis

dblink_close(text cursorname)
+ dblink_close(text connname, text cursorname)

Inputs

+   connname
+     if two arguments are present, the first is taken as the specific
+     connection name to use; otherwise the unnamed connection is assumed
+ 
cursorname

a reference name for the cursor
***************
*** 135,141 ****
Returns status = "OK"

Note
! dblink_connect(text connstr) must be executed first.

Example usage

--- 150,157 ----
Returns status = "OK"

Note
! dblink_connect(text connstr) or dblink_connect(text connname, text connstr)
! must be executed first.

Example usage

***************
*** 157,159 ****
--- 173,192 ----
OK
(1 row)

+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select dblink_open('myconn','foo','select proname, prosrc from pg_proc');
+  dblink_open
+ -------------
+  OK
+ (1 row)
+ 
+ select dblink_close('myconn','foo');
+  dblink_close
+ --------------
+  OK
+ (1 row)
Index: contrib/dblink/doc/deprecated
===================================================================
RCS file: contrib/dblink/doc/deprecated
diff -N contrib/dblink/doc/deprecated
*** contrib/dblink/doc/deprecated	2 Sep 2002 06:32:41 -0000	1.1
--- /dev/null	1 Jan 1970 00:00:00 -0000
***************
*** 1,105 ****
- ==================================================================
- Name
- 
- *DEPRECATED* use new dblink syntax
- dblink -- Returns a resource id for a data set from a remote database
- 
- Synopsis
- 
- dblink(text connstr, text sql)
- 
- Inputs
- 
-   connstr
- 
-     standard libpq format connection srting, 
-     e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
- 
-   sql
- 
-     sql statement that you wish to execute on the remote host
-     e.g. "select * from pg_class"
- 
- Outputs
- 
-   Returns setof int (res_id)
- 
- Example usage
- 
-   select dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                ,'select f1, f2 from mytable');
- 
- ==================================================================
- 
- Name
- 
- *DEPRECATED* use new dblink syntax
- dblink_tok -- Returns individual select field results from a dblink remote query
- 
- Synopsis
- 
- dblink_tok(int res_id, int fnumber)
- 
- Inputs
- 
-   res_id
- 
-     a resource id returned by a call to dblink()
- 
-   fnumber
- 
-     the ordinal position (zero based) of the field to be returned from the dblink result set
- 
- Outputs
- 
-   Returns text
- 
- Example usage
- 
-   select dblink_tok(t1.dblink_p,0) as f1, dblink_tok(t1.dblink_p,1) as f2
-   from (select dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                      ,'select f1, f2 from mytable') as dblink_p) as t1;
- 
- 
- ==================================================================
- *DEPRECATED* use new dblink syntax
- A more convenient way to use dblink may be to create a view:
- 
-  create view myremotetable as
-  select dblink_tok(t1.dblink_p,0) as f1, dblink_tok(t1.dblink_p,1) as f2
-  from (select dblink('hostaddr=127.0.0.1 port=5432 dbname=template1 user=postgres password=postgres'
-                     ,'select proname, prosrc from pg_proc') as dblink_p) as t1;
- 
- Then you can simply write:
- 
-    select f1, f2 from myremotetable where f1 like 'bytea%';
- 
- ==================================================================
- Name
- *DEPRECATED* use new dblink_exec syntax
- dblink_last_oid -- Returns last inserted oid
- 
- Synopsis
- 
- dblink_last_oid(int res_id) RETURNS oid
- 
- Inputs
- 
-   res_id
- 
-     any resource id returned by dblink function;
- 
- Outputs
- 
-   Returns oid of last inserted tuple
- 
- Example usage
- 
- test=# select dblink_last_oid(dblink('hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'
-                ,'insert into mytable (f1, f2) values (1,2)'));
- 
-  dblink_last_oid
- ----------------
-  16553
- (1 row)
- 
--- 0 ----
Index: contrib/dblink/doc/execute
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/execute,v
retrieving revision 1.1
diff -c -r1.1 execute
*** contrib/dblink/doc/execute	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/execute	15 Jun 2003 05:41:10 -0000
***************
*** 6,27 ****
Synopsis

dblink_exec(text connstr, text sql)
! - or -
dblink_exec(text sql)

Inputs

connstr

! standard libpq format connection string,
! e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
! If the second form is used, then the dblink_connect(text connstr) must be
! executed first.

sql

sql statement that you wish to execute on the remote host, e.g.:
-
insert into foo values(0,'a','{"a0","b0","c0"}');

Outputs
--- 6,28 ----
Synopsis

dblink_exec(text connstr, text sql)
! dblink_exec(text connname, text sql)
dblink_exec(text sql)

Inputs

+   connname
connstr
+     If two arguments are present, the first is first assumed to be a specific
+     connection name to use. If the name is not found, the argument is then
+     assumed to be a valid connection string, of standard libpq format,
+     e.g.: "hostaddr=127.0.0.1 dbname=mydb user=postgres password=mypasswd"

! If only one argument is used, then the unnamed connection is used.

sql

sql statement that you wish to execute on the remote host, e.g.:
insert into foo values(0,'a','{"a0","b0","c0"}');

Outputs
***************
*** 36,49 ****

Example usage

! test=# select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)

! test=# select dblink_exec('insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
dblink_exec
-----------------
INSERT 943366 1
(1 row)
--- 37,62 ----

Example usage

! select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)

! select dblink_exec('insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
dblink_exec
-----------------
INSERT 943366 1
+ (1 row)
+ 
+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select dblink_exec('myconn','insert into foo values(21,''z'',''{"a0","b0","c0"}'');');
+    dblink_exec
+ ------------------
+  INSERT 6432584 1
(1 row)
Index: contrib/dblink/doc/query
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/doc/query,v
retrieving revision 1.1
diff -c -r1.1 query
*** contrib/dblink/doc/query	2 Sep 2002 06:32:41 -0000	1.1
--- contrib/dblink/doc/query	15 Jun 2003 05:39:31 -0000
***************
*** 6,22 ****
Synopsis

dblink(text connstr, text sql)
! - or -
dblink(text sql)

Inputs

connstr

! standard libpq format connection string,
! e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
! If the second form is used, then the dblink_connect(text connstr) must be
! executed first.

sql

--- 6,24 ----
Synopsis

dblink(text connstr, text sql)
! dblink(text connname, text sql)
dblink(text sql)

Inputs

+   connname
connstr
+     If two arguments are present, the first is first assumed to be a specific
+     connection name to use. If the name is not found, the argument is then
+     assumed to be a valid connection string, of standard libpq format,
+     e.g.: "hostaddr=127.0.0.1 dbname=mydb user=postgres password=mypasswd"

! If only one argument is used, then the unnamed connection is used.

sql

***************
*** 29,35 ****

Example usage

! test=# select * from dblink('dbname=template1','select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
--- 31,37 ----

Example usage

! select * from dblink('dbname=template1','select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname | prosrc
------------+------------
***************
*** 47,59 ****
byteaout | byteaout
(12 rows)

! test=# select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
(1 row)

! test=# select * from dblink('select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
--- 49,61 ----
byteaout   | byteaout
(12 rows)

! select dblink_connect('dbname=template1');
dblink_connect
----------------
OK
(1 row)

! select * from dblink('select proname, prosrc from pg_proc')
as t1(proname name, prosrc text) where proname like 'bytea%';
proname   |   prosrc
------------+------------
***************
*** 70,75 ****
--- 72,104 ----
byteain    | byteain
byteaout   | byteaout
(12 rows)
+ 
+ select dblink_connect('myconn','dbname=regression');
+  dblink_connect
+ ----------------
+  OK
+ (1 row)
+ 
+ select * from dblink('myconn','select proname, prosrc from pg_proc')
+  as t1(proname name, prosrc text) where proname like 'bytea%';
+   proname   |   prosrc
+ ------------+------------
+  bytearecv  | bytearecv
+  byteasend  | byteasend
+  byteale    | byteale
+  byteagt    | byteagt
+  byteage    | byteage
+  byteane    | byteane
+  byteacmp   | byteacmp
+  bytealike  | bytealike
+  byteanlike | byteanlike
+  byteacat   | byteacat
+  byteaeq    | byteaeq
+  bytealt    | bytealt
+  byteain    | byteain
+  byteaout   | byteaout
+ (14 rows)
+ 

==================================================================
A more convenient way to use dblink may be to create a view:
Index: contrib/dblink/expected/dblink.out
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/expected/dblink.out,v
retrieving revision 1.8
diff -c -r1.8 dblink.out
*** contrib/dblink/expected/dblink.out	14 May 2003 03:25:55 -0000	1.8
--- contrib/dblink/expected/dblink.out	15 Jun 2003 04:11:11 -0000
***************
*** 106,116 ****
9 | j | {a9,b9,c9}
(2 rows)

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: no connection available
-- create a persistent connection
SELECT dblink_connect('dbname=regression');
dblink_connect 
--- 106,116 ----
9 | j | {a9,b9,c9}
(2 rows)

! -- should generate "connection not available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR: dblink_record: connection not available
-- create a persistent connection
SELECT dblink_connect('dbname=regression');
dblink_connect
***************
*** 172,181 ****
OK
(1 row)

! -- should generate "cursor rmt_foo_cursor does not exist" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);
! ERROR:  dblink_fetch: cursor rmt_foo_cursor does not exist
-- close the persistent connection
SELECT dblink_disconnect();
dblink_disconnect 
--- 172,181 ----
OK
(1 row)

! -- should generate "cursor not found: rmt_foo_cursor" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);
! ERROR: dblink_fetch: cursor not found: rmt_foo_cursor
-- close the persistent connection
SELECT dblink_disconnect();
dblink_disconnect
***************
*** 183,193 ****
OK
(1 row)

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: no connection available
-- put more data into our slave table, first using arbitrary connection syntax
-- but truncate the actual return value so we can use diff to check for success
SELECT substr(dblink_exec('dbname=regression','INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
--- 183,194 ----
OK
(1 row)

! -- should generate "no connection to the server" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
! ERROR:  dblink: sql error: no connection to the server
! 
-- put more data into our slave table, first using arbitrary connection syntax
-- but truncate the actual return value so we can use diff to check for success
SELECT substr(dblink_exec('dbname=regression','INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
***************
*** 268,270 ****
--- 269,466 ----
OK
(1 row)

+ --
+ -- tests for the new named persistent connection syntax
+ --
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ ERROR:  dblink: connection error: missing "=" after "myconn" in connection info string
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- use the named persistent connection
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- create a second named persistent connection
+ -- should error with "cannot save named connection"
+ SELECT dblink_connect('myconn','dbname=regression');
+ NOTICE:  cannot use a connection name more than once
+ ERROR:  dblink_connect: cannot save named connection
+ -- create a second named persistent connection with a new name
+ SELECT dblink_connect('myconn2','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- use the second named persistent connection
+ SELECT *
+ FROM dblink('myconn2','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- close the second named persistent connection
+ SELECT dblink_disconnect('myconn2');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- open a cursor
+ SELECT dblink_open('myconn','rmt_foo_cursor','SELECT * FROM foo');
+  dblink_open 
+ -------------
+  OK
+ (1 row)
+ 
+ -- fetch some data
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a | b |     c      
+ ---+---+------------
+  0 | a | {a0,b0,c0}
+  1 | b | {a1,b1,c1}
+  2 | c | {a2,b2,c2}
+  3 | d | {a3,b3,c3}
+ (4 rows)
+ 
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a | b |     c      
+ ---+---+------------
+  4 | e | {a4,b4,c4}
+  5 | f | {a5,b5,c5}
+  6 | g | {a6,b6,c6}
+  7 | h | {a7,b7,c7}
+ (4 rows)
+ 
+ -- this one only finds three rows left
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+  a  | b |       c       
+ ----+---+---------------
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+ (3 rows)
+ 
+ -- close the cursor
+ SELECT dblink_close('myconn','rmt_foo_cursor');
+  dblink_close 
+ --------------
+  OK
+ (1 row)
+ 
+ -- should generate "cursor not found: rmt_foo_cursor" error
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ ERROR:  dblink_fetch: cursor not found: rmt_foo_cursor
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ ERROR:  dblink: connection error: missing "=" after "myconn" in connection info string
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+  dblink_connect 
+ ----------------
+  OK
+ (1 row)
+ 
+ -- put more data into our slave table, using named persistent connection syntax
+ -- but truncate the actual return value so we can use diff to check for success
+ SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
+  substr 
+ --------
+  INSERT
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[]);
+  a  | b |       c       
+ ----+---+---------------
+   0 | a | {a0,b0,c0}
+   1 | b | {a1,b1,c1}
+   2 | c | {a2,b2,c2}
+   3 | d | {a3,b3,c3}
+   4 | e | {a4,b4,c4}
+   5 | f | {a5,b5,c5}
+   6 | g | {a6,b6,c6}
+   7 | h | {a7,b7,c7}
+   8 | i | {a8,b8,c8}
+   9 | j | {a9,b9,c9}
+  10 | k | {a10,b10,c10}
+  11 | l | {a11,b11,c11}
+ (12 rows)
+ 
+ -- change some data
+ SELECT dblink_exec('myconn','UPDATE foo SET f3[2] = ''b99'' WHERE f1 = 11');
+  dblink_exec 
+ -------------
+  UPDATE 1
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+  a  | b |       c       
+ ----+---+---------------
+  11 | l | {a11,b99,c11}
+ (1 row)
+ 
+ -- delete some data
+ SELECT dblink_exec('myconn','DELETE FROM foo WHERE f1 = 11');
+  dblink_exec 
+ -------------
+  DELETE 1
+ (1 row)
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+  a | b | c 
+ ---+---+---
+ (0 rows)
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+  dblink_disconnect 
+ -------------------
+  OK
+ (1 row)
+ 
+ -- close the named persistent connection again
+ -- should get "connection named "myconn" not found" error
+ SELECT dblink_disconnect('myconn');
+ ERROR:  dblink_disconnect: connection named "myconn" not found
Index: contrib/dblink/sql/dblink.sql
===================================================================
RCS file: /opt/src/cvs/pgsql-server/contrib/dblink/sql/dblink.sql,v
retrieving revision 1.8
diff -c -r1.8 dblink.sql
*** contrib/dblink/sql/dblink.sql	14 May 2003 03:25:55 -0000	1.8
--- contrib/dblink/sql/dblink.sql	15 Jun 2003 04:10:59 -0000
***************
*** 68,74 ****
FROM dblink('dbname=regression','SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
--- 68,74 ----
FROM dblink('dbname=regression','SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;

! -- should generate "connection not available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
***************
*** 98,111 ****
-- close the cursor
SELECT dblink_close('rmt_foo_cursor');

! -- should generate "cursor rmt_foo_cursor does not exist" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);

-- close the persistent connection
SELECT dblink_disconnect();

! -- should generate "no connection available" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
--- 98,111 ----
-- close the cursor
SELECT dblink_close('rmt_foo_cursor');

! -- should generate "cursor not found: rmt_foo_cursor" error
SELECT *
FROM dblink_fetch('rmt_foo_cursor',4) AS t(a int, b text, c text[]);

-- close the persistent connection
SELECT dblink_disconnect();

! -- should generate "no connection to the server" error
SELECT *
FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
WHERE t.a > 7;
***************
*** 143,145 ****
--- 143,240 ----

-- close the persistent connection
SELECT dblink_disconnect();
+ 
+ --
+ -- tests for the new named persistent connection syntax
+ --
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- use the named persistent connection
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a second named persistent connection
+ -- should error with "cannot save named connection"
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- create a second named persistent connection with a new name
+ SELECT dblink_connect('myconn2','dbname=regression');
+ 
+ -- use the second named persistent connection
+ SELECT *
+ FROM dblink('myconn2','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- close the second named persistent connection
+ SELECT dblink_disconnect('myconn2');
+ 
+ -- open a cursor
+ SELECT dblink_open('myconn','rmt_foo_cursor','SELECT * FROM foo');
+ 
+ -- fetch some data
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- this one only finds three rows left
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- close the cursor
+ SELECT dblink_close('myconn','rmt_foo_cursor');
+ 
+ -- should generate "cursor not found: rmt_foo_cursor" error
+ SELECT *
+ FROM dblink_fetch('myconn','rmt_foo_cursor',4) AS t(a int, b text, c text[]);
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+ 
+ -- should generate "missing "=" after "myconn" in connection info string" error
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE t.a > 7;
+ 
+ -- create a named persistent connection
+ SELECT dblink_connect('myconn','dbname=regression');
+ 
+ -- put more data into our slave table, using named persistent connection syntax
+ -- but truncate the actual return value so we can use diff to check for success
+ SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[]);
+ 
+ -- change some data
+ SELECT dblink_exec('myconn','UPDATE foo SET f3[2] = ''b99'' WHERE f1 = 11');
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+ 
+ -- delete some data
+ SELECT dblink_exec('myconn','DELETE FROM foo WHERE f1 = 11');
+ 
+ -- let's see it
+ SELECT *
+ FROM dblink('myconn','SELECT * FROM foo') AS t(a int, b text, c text[])
+ WHERE a = 11;
+ 
+ -- close the named persistent connection
+ SELECT dblink_disconnect('myconn');
+ 
+ -- close the named persistent connection again
+ -- should get "connection named "myconn" not found" error
+ SELECT dblink_disconnect('myconn');

---------------------------(end of broadcast)---------------------------
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-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
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  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073