Cleaner solution to the problem of loading pre-7.3 dumps containing

columns of type lo (see contrib/lo).  Rather than hacking the function
definitions on-the-fly, just modify the queries issued by FixupBlobRefs
so that they work even if CREATE CAST hasn't been issued.

src/bin/pg_dump/pg_backup_archiver.c

@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *		$Header: /cvsroot/pgsql/src/bin/pg_dump/pg_backup_archiver.c,v 1.66 2003/01/27 00:23:38 tgl Exp $
+ *		$Header: /cvsroot/pgsql/src/bin/pg_dump/pg_backup_archiver.c,v 1.67 2003/02/01 22:06:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -122,102 +122,6 @@ CloseArchive(Archive *AHX)
 		die_horribly(AH, modulename, "could not close the output file in CloseArchive\n");
 }
 
-/*
- *	This function repairs a slip when upgrading PG cast
- *	mechanism from 7.2 or earlier to 7.3 or later.
- *	The casts between lo and oid are needed when retrieving
- *	lo type data in FixupBlobRefs and so adjust lo type in
- *	contrib before processing FixupBlobRefs.
- */
-static void
-Adjust_lo_type(ArchiveHandle *AH)
-{
-	PGresult   *res;
-	int	nTuples;
-
-	/*
-	 *	First check the existence of the cast oid as lo.
-	 */
-	res = PQexec(AH->blobConnection, "select 1 from pg_cast where"
-		" castsource in (select oid from pg_type where typname = 'oid')"
-		" and casttarget in (select oid from pg_type where typname = 'lo')");
-
-	if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
-		die_horribly(AH, modulename, "error while checking the cast oid as lo\n");
-	nTuples = PQntuples(res);
-	PQclear(res);
-	if (nTuples == 0)
-	{
-		/*
-	 	 *	Check the existence of the cast function lo(oid)
-		 *	and change it to be IMMUTABLE.
-	 	 */
-		res = PQexec(AH->blobConnection, "update pg_proc set provolatile = 'i'"
-			" where proname = 'lo'"
-			" and pronargs = 1"
-			" and prorettype in (select oid from pg_type where typname = 'lo')"
-			" and proargtypes[0] in (select oid from pg_type where typname = 'oid')");
-
-		if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
-			die_horribly(AH, modulename, "could not adjust lo(oid) function\n");
-		nTuples = atoi(PQcmdTuples(res));
-		PQclear(res);
-		if (nTuples == 1)
-		{
-			/*
-			 *	The cast function lo(oid) exists and
-			 *	then create the correspoding cast.
-			 */
-			res = PQexec(AH->blobConnection, "create cast"
-				" (oid as lo) with function lo(oid) as implicit");
-			if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
-				die_horribly(AH, modulename, "couldn't create cast (oid as lo)\n");
-			PQclear(res);
-		}
-	}
-
-	/*
-	 *	Also check the existence of the cast lo as oid.
-	 */
-	res = PQexec(AH->blobConnection, "select 1 from pg_cast where"
-		" castsource in (select oid from pg_type where typname = 'lo')"
-		" and casttarget in (select oid from pg_type where typname = 'oid')");
-
-	if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
-		die_horribly(AH, modulename, "error while checking the cast lo as oid\n");
-	nTuples = PQntuples(res);
-	PQclear(res);
-	if (nTuples == 0)
-	{
-		/*
-	 	 *	Check the existence of the cast function oid(lo)
-		 *	and change it to be IMMUTABLE.
-	 	 */
-		res = PQexec(AH->blobConnection, "update pg_proc set provolatile = 'i'"
-			" where proname = 'oid'"
-			" and pronargs = 1"
-			" and prorettype in (select oid from pg_type where typname = 'oid')"
-			" and proargtypes[0] in (select oid from pg_type where typname = 'lo')");
-
-		if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
-			die_horribly(AH, modulename, "could not adjust oid(lo) function\n");
-		nTuples = atoi(PQcmdTuples(res));
-		PQclear(res);
-		if (nTuples == 1)
-		{
-			/*
-			 *	The cast function oid(lo) exists and
-			 *	then create the correspoding cast.
-			 */
-			res = PQexec(AH->blobConnection, "create cast"
-				" (lo as oid) with function oid(lo) as implicit");
-			if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
-				die_horribly(AH, modulename, "couldn't create cast (lo as oid)\n");
-			PQclear(res);
-		}
-	}
-}
-
 /* Public */
 void
 RestoreArchive(Archive *AHX, RestoreOptions *ropt)
@@ -453,7 +357,6 @@ RestoreArchive(Archive *AHX, RestoreOptions *ropt)
 		/* NULL parameter means disable ALL user triggers */
 		_disableTriggersIfNecessary(AH, NULL, ropt);
 
-		Adjust_lo_type(AH);
 		te = AH->toc->next;
 		while (te != AH->toc)
 		{

src/bin/pg_dump/pg_backup_db.c

@@ -5,7 +5,7 @@
  *	Implements the basic DB functions used by the archiver.
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_backup_db.c,v 1.43 2002/10/22 19:15:23 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_backup_db.c,v 1.44 2003/02/01 22:06:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -589,7 +589,6 @@ FixupBlobRefs(ArchiveHandle *AH, TocEntry *te)
 			   *uRes;
 	int			i,
 				n;
-	char	   *attr;
 
 	if (strcmp(te->tag, BLOB_XREF_TABLE) == 0)
 		return;
@@ -604,7 +603,7 @@ FixupBlobRefs(ArchiveHandle *AH, TocEntry *te)
 					  fmtId(te->tag));
 
 	appendPQExpBuffer(tblQry,
-					  "SELECT a.attname FROM "
+					  "SELECT a.attname, t.typname FROM "
 					  "pg_catalog.pg_attribute a, pg_catalog.pg_type t "
 		 "WHERE a.attnum > 0 AND a.attrelid = '%s'::pg_catalog.regclass "
 				 "AND a.atttypid = t.oid AND t.typname in ('oid', 'lo')",
@@ -623,22 +622,52 @@ FixupBlobRefs(ArchiveHandle *AH, TocEntry *te)
 
 	for (i = 0; i < n; i++)
 	{
+		char	   *attr;
+		char	   *typname;
+		bool		typeisoid;
+
 		attr = PQgetvalue(res, i, 0);
+		typname = PQgetvalue(res, i, 1);
+
+		typeisoid = (strcmp(typname, "oid") == 0);
 
 		ahlog(AH, 1, "fixing large object cross-references for %s.%s\n",
 			  te->tag, attr);
 
 		resetPQExpBuffer(tblQry);
 
-		/* Can't use fmtId twice in one call... */
+		/*
+		 * Note: we use explicit typename() cast style here because if we
+		 * are dealing with a dump from a pre-7.3 database containing LO
+		 * columns, the dump probably will not have CREATE CAST commands
+		 * for lo<->oid conversions.  What it will have is functions,
+		 * which we will invoke as functions.
+		 */
+
+		/* Can't use fmtId more than once per call... */
+		appendPQExpBuffer(tblQry,
+						  "UPDATE %s SET %s = ",
+						  tblName->data, fmtId(attr));
+		if (typeisoid)
 			appendPQExpBuffer(tblQry,
-						  "UPDATE %s SET %s = %s.newOid",
-						  tblName->data, fmtId(attr),
+							  "%s.newOid",
 							  BLOB_XREF_TABLE);
+		else
 			appendPQExpBuffer(tblQry,
-						  " FROM %s WHERE %s.oldOid = %s.%s",
-						  BLOB_XREF_TABLE,
+							  "%s(%s.newOid)",
+							  fmtId(typname),
+							  BLOB_XREF_TABLE);
+		appendPQExpBuffer(tblQry,
+						  " FROM %s WHERE %s.oldOid = ",
 						  BLOB_XREF_TABLE,
+						  BLOB_XREF_TABLE);
+		if (typeisoid)
+			appendPQExpBuffer(tblQry,
+							  "%s.%s",
+							  tblName->data, fmtId(attr));
+		else
+			appendPQExpBuffer(tblQry,
+							  "oid(%s.%s)",
 							  tblName->data, fmtId(attr));
 
 		ahlog(AH, 10, "SQL: %s\n", tblQry->data);