Add GUC parameter check_function_bodies to control whether validation

of function bodies is done at CREATE FUNCTION time.  This is normally
true but can be set false to avoid problems with forward references,
wrong schema search path, etc.  This is just the backend patch, still
need to adjust pg_dump to make use of it.

doc/src/sgml/runtime.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.209 2003/09/20 20:12:05 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.210 2003/10/03 19:26:49 tgl Exp $
 -->
 
 <Chapter Id="runtime">
@@ -2085,6 +2085,17 @@ SET ENABLE_SEQSCAN TO OFF;
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><varname>check_function_bodies</varname> (<type>boolean</type>)</term>
+      <listitem>
+       <para>
+        This parameter is normally true.  When set false, it disables
+	validation of the function body string in <command>CREATE FUNCTION</>.
+	Disabling validation is occasionally useful to avoid problems such as
+	forward references when restoring function definitions from a dump.
+       </para>
+      </listitem>
+     </varlistentry>
 
      <varlistentry>
       <indexterm>

src/backend/catalog/pg_proc.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_proc.c,v 1.108 2003/09/29 00:05:24 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/catalog/pg_proc.c,v 1.109 2003/10/03 19:26:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -34,6 +34,10 @@
 #include "utils/syscache.h"
 
 
+/* GUC parameter */
+bool		check_function_bodies = true;
+
+
 Datum		fmgr_internal_validator(PG_FUNCTION_ARGS);
 Datum		fmgr_c_validator(PG_FUNCTION_ARGS);
 Datum		fmgr_sql_validator(PG_FUNCTION_ARGS);
@@ -560,6 +564,11 @@ fmgr_internal_validator(PG_FUNCTION_ARGS)
 	Datum		tmp;
 	char	   *prosrc;
 
+	/*
+	 * We do not honor check_function_bodies since it's unlikely the
+	 * function name will be found later if it isn't there now.
+	 */
+
 	tuple = SearchSysCache(PROCOID,
 						   ObjectIdGetDatum(funcoid),
 						   0, 0, 0);
@@ -604,6 +613,12 @@ fmgr_c_validator(PG_FUNCTION_ARGS)
 	char	   *prosrc;
 	char	   *probin;
 
+	/*
+	 * It'd be most consistent to skip the check if !check_function_bodies,
+	 * but the purpose of that switch is to be helpful for pg_dump loading,
+	 * and for pg_dump loading it's much better if we *do* check.
+	 */
+
 	tuple = SearchSysCache(PROCOID,
 						   ObjectIdGetDatum(funcoid),
 						   0, 0, 0);
@@ -633,8 +648,7 @@ fmgr_c_validator(PG_FUNCTION_ARGS)
 /*
  * Validator for SQL language functions
  *
- * Parse it here in order to be sure that it contains no syntax
- * errors.
+ * Parse it here in order to be sure that it contains no syntax errors.
  */
 Datum
 fmgr_sql_validator(PG_FUNCTION_ARGS)
@@ -689,6 +703,9 @@ fmgr_sql_validator(PG_FUNCTION_ARGS)
 		}
 	}
 
+	/* Postpone body checks if !check_function_bodies */
+	if (check_function_bodies)
+	{
 		tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
 		if (isnull)
 			elog(ERROR, "null prosrc");
@@ -698,11 +715,11 @@ fmgr_sql_validator(PG_FUNCTION_ARGS)
 		/*
 		 * We can't do full prechecking of the function definition if there
 		 * are any polymorphic input types, because actual datatypes of
-	 * expression results will be unresolvable.  The check will be done at
-	 * runtime instead.
+		 * expression results will be unresolvable.  The check will be done
+		 * at runtime instead.
 		 *
-	 * We can run the text through the raw parser though; this will at least
-	 * catch silly syntactic errors.
+		 * We can run the text through the raw parser though; this will at
+		 * least catch silly syntactic errors.
 		 */
 		if (!haspolyarg)
 		{
@@ -713,6 +730,7 @@ fmgr_sql_validator(PG_FUNCTION_ARGS)
 		}
 		else
 			querytree_list = pg_parse_query(prosrc);
+	}
 
 	ReleaseSysCache(tuple);
 

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.161 2003/09/29 00:05:25 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.162 2003/10/03 19:26:49 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -66,6 +66,7 @@
 
 /* XXX these should appear in other modules' header files */
 extern bool Log_connections;
+extern bool check_function_bodies;
 extern int	PreAuthDelay;
 extern int	AuthenticationTimeout;
 extern int	CheckPointTimeout;
@@ -821,6 +822,14 @@ static struct config_bool ConfigureNamesBool[] =
 		&add_missing_from,
 		true, NULL, NULL
 	},
+	{
+		{"check_function_bodies", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("check function bodies during CREATE FUNCTION"),
+			NULL
+		},
+		&check_function_bodies,
+		true, NULL, NULL
+	},
 
 	/* End-of-list marker */
 	{

src/backend/utils/misc/postgresql.conf.sample

@@ -205,6 +205,7 @@
 # - Statement Behavior -
 
 #search_path = '$user,public'	# schema names
+#check_function_bodies = true
 #default_transaction_isolation = 'read committed'
 #default_transaction_read_only = false
 #statement_timeout = 0		# 0 is disabled, in milliseconds