Remove the DELETEs from pg_shadow and pg_group that pg_dumpall used to

emit when given the --clean option, in favor of individual DROP ROLE
commands.  The old technique could not possibly work in 8.1, and was
never a very good idea anyway IMHO.  The DROP ROLE approach has the
defect that the DROPs will fail for roles that own objects or have
privileges, but perhaps we can improve that later.

doc/src/sgml/ref/pg_dumpall.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/pg_dumpall.sgml,v 1.52 2005/07/25 22:12:31 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/pg_dumpall.sgml,v 1.53 2005/10/10 22:29:47 tgl Exp $
 PostgreSQL documentation
 -->
 
@@ -90,8 +90,9 @@ PostgreSQL documentation
       <term><option>--clean</option></term>
       <listitem>
        <para>
-        Include SQL commands to clean (drop) the databases before
-        recreating them.
+        Include SQL commands to clean (drop) databases before
+        recreating them.  <command>DROP</> commands for roles and
+        tablespaces are added as well.
        </para>
       </listitem>
      </varlistentry>

src/bin/pg_dump/pg_dumpall.c

@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *
- * $PostgreSQL: pgsql/src/bin/pg_dump/pg_dumpall.c,v 1.67 2005/08/28 16:31:37 tgl Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_dump/pg_dumpall.c,v 1.68 2005/10/10 22:29:48 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,7 +42,7 @@ static const char *progname;
 
 static void help(void);
 
-static void dumpRoles(PGconn *conn, bool initdbonly);
+static void dumpRoles(PGconn *conn);
 static void dumpRoleMembership(PGconn *conn);
 static void dumpGroups(PGconn *conn);
 static void dumpTablespaces(PGconn *conn);
@@ -316,8 +316,8 @@ main(int argc, char *argv[])
 
 	if (!data_only)
 	{
-		/* Dump all users excluding the initdb user */
-		dumpRoles(conn, false);
+		/* Dump roles (users) */
+		dumpRoles(conn);
 
 		/* Dump role memberships --- need different method for pre-8.1 */
 		if (server_version >= 80100)
@@ -325,14 +325,13 @@ main(int argc, char *argv[])
 		else
 			dumpGroups(conn);
 
+		/* Dump tablespaces */
 		if (server_version >= 80000)
 			dumpTablespaces(conn);
 
+		/* Dump CREATE DATABASE commands */
 		if (!globals_only)
 			dumpCreateDB(conn);
-
-		/* Dump alter command for initdb user */
-		dumpRoles(conn, true);
 	}
 
 	if (!globals_only)
@@ -394,11 +393,9 @@ help(void)
 
 /*
  * Dump roles
- *
- * Is able to dump all non initdb users or just the initdb user.
  */
 static void
-dumpRoles(PGconn *conn, bool initdbonly)
+dumpRoles(PGconn *conn)
 {
 	PQExpBuffer buf = createPQExpBuffer();
 	PGresult   *res;
@@ -411,8 +408,7 @@ dumpRoles(PGconn *conn, bool initdbonly)
 				i_rolcanlogin,
 				i_rolconnlimit,
 				i_rolpassword,
-				i_rolvaliduntil,
-				i_clusterowner;
+				i_rolvaliduntil;
 	int			i;
 
 	/* note: rolconfig is dumped later */
@@ -421,8 +417,7 @@ dumpRoles(PGconn *conn, bool initdbonly)
 						  "SELECT rolname, rolsuper, rolinherit, "
 						  "rolcreaterole, rolcreatedb, rolcatupdate, "
 						  "rolcanlogin, rolconnlimit, rolpassword, "
-						  "rolvaliduntil, "
-						  "(oid = (SELECT datdba FROM pg_database WHERE datname = 'template0')) AS clusterowner "
+						  "rolvaliduntil "
 						  "FROM pg_authid");
 	else
 		printfPQExpBuffer(buf,
@@ -435,8 +430,7 @@ dumpRoles(PGconn *conn, bool initdbonly)
 						  "true as rolcanlogin, "
 						  "-1 as rolconnlimit, "
 						  "passwd as rolpassword, "
-						  "valuntil as rolvaliduntil, "
-						  "(usesysid = (SELECT datdba FROM pg_database WHERE datname = '%s')) AS clusterowner "
+						  "valuntil as rolvaliduntil "
 						  "FROM pg_shadow "
 						  "UNION ALL "
 						  "SELECT groname as rolname, "
@@ -448,10 +442,8 @@ dumpRoles(PGconn *conn, bool initdbonly)
 						  "false as rolcanlogin, "
 						  "-1 as rolconnlimit, "
 						  "null::text as rolpassword, "
-						  "null::abstime as rolvaliduntil, "
-						  "false AS clusterowner "
-						  "FROM pg_group",
-						  (server_version >= 70100) ? "template0" : "template1");
+						  "null::abstime as rolvaliduntil "
+						  "FROM pg_group");
 
 	res = executeQuery(conn, buf->data);
 
@@ -465,33 +457,29 @@ dumpRoles(PGconn *conn, bool initdbonly)
 	i_rolconnlimit = PQfnumber(res, "rolconnlimit");
 	i_rolpassword = PQfnumber(res, "rolpassword");
 	i_rolvaliduntil = PQfnumber(res, "rolvaliduntil");
-	i_clusterowner = PQfnumber(res, "clusterowner");
 
-	if (PQntuples(res) > 0 || (!initdbonly && output_clean))
+	if (PQntuples(res) > 0)
 		printf("--\n-- Roles\n--\n\n");
-	if (!initdbonly && output_clean)
-		printf("DELETE FROM pg_shadow WHERE usesysid <> (SELECT datdba FROM pg_database WHERE datname = 'template0');\n\n");
 
 	for (i = 0; i < PQntuples(res); i++)
 	{
 		const char *rolename;
-		bool		clusterowner;
 
 		rolename = PQgetvalue(res, i, i_rolname);
-		clusterowner = (strcmp(PQgetvalue(res, i, i_clusterowner), "t") == 0);
 
-		/* Check which pass we're on */
-		if ((initdbonly && !clusterowner) || (!initdbonly && clusterowner))
-			continue;
+		resetPQExpBuffer(buf);
+
+		if (output_clean)
+			appendPQExpBuffer(buf, "DROP ROLE %s;\n", fmtId(rolename));
 
 		/*
-		 * Dump ALTER ROLE for the cluster owner and CREATE ROLE for all
-		 * other roles
+		 * We dump CREATE ROLE followed by ALTER ROLE to ensure that the
+		 * role will acquire the right properties even if it already exists.
+		 * (The above DROP may therefore seem redundant, but it isn't really,
+		 * because this technique doesn't get rid of role memberships.)
 		 */
-		if (!clusterowner)
-			printfPQExpBuffer(buf, "CREATE ROLE %s WITH", fmtId(rolename));
-		else
-			printfPQExpBuffer(buf, "ALTER ROLE %s WITH", fmtId(rolename));
+		appendPQExpBuffer(buf, "CREATE ROLE %s;\n", fmtId(rolename));
+		appendPQExpBuffer(buf, "ALTER ROLE %s WITH", fmtId(rolename));
 
 		if (strcmp(PQgetvalue(res, i, i_rolsuper), "t") == 0)
 			appendPQExpBuffer(buf, " SUPERUSER");
@@ -569,10 +557,8 @@ dumpRoleMembership(PGconn *conn)
 					   "LEFT JOIN pg_authid um on um.oid = a.member "
 					   "LEFT JOIN pg_authid ug on ug.oid = a.grantor");
 
-	if (PQntuples(res) > 0 || output_clean)
+	if (PQntuples(res) > 0)
 		printf("--\n-- Role memberships\n--\n\n");
-	if (output_clean)
-		printf("DELETE FROM pg_auth_members;\n\n");
 
 	for (i = 0; i < PQntuples(res); i++)
 	{
@@ -610,10 +596,8 @@ dumpGroups(PGconn *conn)
 
 	res = executeQuery(conn, "SELECT groname, grolist FROM pg_group");
 
-	if (PQntuples(res) > 0 || output_clean)
+	if (PQntuples(res) > 0)
 		printf("--\n-- Role memberships\n--\n\n");
-	if (output_clean)
-		printf("DELETE FROM pg_auth_members;\n\n");
 
 	for (i = 0; i < PQntuples(res); i++)
 	{