Clarify pg_upgrade error message that the 'postgres' database must exist

in the old cluster.

diff --git a/contrib/pg_upgrade/check.c b/contrib/pg_upgrade/check.c
index 5b9b4cd3d5a3541eb9c971b6914bdbb080c61a04..e400814617b82c9561692d2303afa7e90d994dbe 100644 (file)
--- a/contrib/pg_upgrade/check.c
+++ b/contrib/pg_upgrade/check.c
@@ -403,8 +403,13 @@ check_old_cluster_has_new_cluster_dbs(void)
                                           new_cluster.dbarr.dbs[new_dbnum].db_name) == 0)
                                break;
                if (old_dbnum == old_cluster.dbarr.ndbs)
-                       pg_log(PG_FATAL, "New cluster database \"%s\" does not exist in the old cluster\n",
-                                  new_cluster.dbarr.dbs[new_dbnum].db_name);
+               {
+                       if (strcmp(new_cluster.dbarr.dbs[new_dbnum].db_name, "postgres") == 0)
+                               pg_log(PG_FATAL, "The \"postgres\" database must exist in the old cluster\n");
+                       else
+                               pg_log(PG_FATAL, "New cluster database \"%s\" does not exist in the old cluster\n",
+                                          new_cluster.dbarr.dbs[new_dbnum].db_name);
+               }
        }
 }