Allow pg_upgrade to upgrade an old cluster that doesn't have a

'postgres' database.

diff --git a/contrib/pg_upgrade/check.c b/contrib/pg_upgrade/check.c
index e400814617b82c9561692d2303afa7e90d994dbe..d32a84c6354eae4694a3dadf57faa595e8c33dc4 100644 (file)
--- a/contrib/pg_upgrade/check.c
+++ b/contrib/pg_upgrade/check.c
@@ -14,7 +14,6 @@
 
 static void set_locale_and_encoding(ClusterInfo *cluster);
 static void check_new_cluster_is_empty(void);
-static void check_old_cluster_has_new_cluster_dbs(void);
 static void check_locale_and_encoding(ControlData *oldctrl,
                                                  ControlData *newctrl);
 static void check_is_super_user(ClusterInfo *cluster);
@@ -127,7 +126,6 @@ check_new_cluster(void)
 
        check_new_cluster_is_empty();
        check_for_prepared_transactions(&new_cluster);
-       check_old_cluster_has_new_cluster_dbs();
 
        check_loadable_libraries();
 
@@ -381,39 +379,6 @@ check_new_cluster_is_empty(void)
 }
 
 
-/*
- *     If someone removes the 'postgres' database from the old cluster and
- *     the new cluster has a 'postgres' database, the number of databases
- *     will not match.  We actually could upgrade such a setup, but it would
- *     violate the 1-to-1 mapping of database counts, so we throw an error
- *     instead.  We would detect this as a database count mismatch during
- *     upgrade, but we want to detect it during the check phase and report
- *     the database name.
- */
-static void
-check_old_cluster_has_new_cluster_dbs(void)
-{
-       int                     old_dbnum,
-                               new_dbnum;
-
-       for (new_dbnum = 0; new_dbnum < new_cluster.dbarr.ndbs; new_dbnum++)
-       {
-               for (old_dbnum = 0; old_dbnum < old_cluster.dbarr.ndbs; old_dbnum++)
-                       if (strcmp(old_cluster.dbarr.dbs[old_dbnum].db_name,
-                                          new_cluster.dbarr.dbs[new_dbnum].db_name) == 0)
-                               break;
-               if (old_dbnum == old_cluster.dbarr.ndbs)
-               {
-                       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);
-               }
-       }
-}
-
-
 /*
  * create_script_for_old_cluster_deletion()
  *
@@ -462,7 +427,7 @@ create_script_for_old_cluster_deletion(char **deletion_script_file_name)
                                fprintf(script, RM_CMD " %s%s/PG_VERSION\n",
                                 os_info.tablespaces[tblnum], old_cluster.tablespace_suffix);
 
-                       for (dbnum = 0; dbnum < new_cluster.dbarr.ndbs; dbnum++)
+                       for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
                        {
                                fprintf(script, RMDIR_CMD " %s%s/%d\n",
                                  os_info.tablespaces[tblnum], old_cluster.tablespace_suffix,

diff --git a/contrib/pg_upgrade/function.c b/contrib/pg_upgrade/function.c
index 0f8008951ab2f5fcacd61a94ed503b62e1e6d71b..b154f033e6e338e15c323dcd8c790552b0bc92d4 100644 (file)
--- a/contrib/pg_upgrade/function.c
+++ b/contrib/pg_upgrade/function.c
@@ -132,8 +132,7 @@ get_loadable_libraries(void)
        int                     totaltups;
        int                     dbnum;
 
-       ress = (PGresult **)
-               pg_malloc(old_cluster.dbarr.ndbs * sizeof(PGresult *));
+       ress = (PGresult **) pg_malloc(old_cluster.dbarr.ndbs * sizeof(PGresult *));
        totaltups = 0;
 
        /* Fetch all library names, removing duplicates within each DB */

diff --git a/contrib/pg_upgrade/relfilenode.c b/contrib/pg_upgrade/relfilenode.c
index 1aefd337f1fc0839211d1ae0c0d1c8bfd447bfd7..ad893be1c7fa240180b2cad519806516050f886b 100644 (file)
--- a/contrib/pg_upgrade/relfilenode.c
+++ b/contrib/pg_upgrade/relfilenode.c
@@ -34,22 +34,30 @@ const char *
 transfer_all_new_dbs(DbInfoArr *old_db_arr,
                                   DbInfoArr *new_db_arr, char *old_pgdata, char *new_pgdata)
 {
-       int                     dbnum;
+       int                     old_dbnum, new_dbnum;
        const char *msg = NULL;
 
        prep_status("Restoring user relation files\n");
 
-       if (old_db_arr->ndbs != new_db_arr->ndbs)
-               pg_log(PG_FATAL, "old and new clusters have a different number of databases\n");
-
-       for (dbnum = 0; dbnum < old_db_arr->ndbs; dbnum++)
+       /* Scan the old cluster databases and transfer their files */
+       for (old_dbnum = new_dbnum = 0;
+                old_dbnum < old_db_arr->ndbs && new_dbnum < new_db_arr->ndbs;
+                old_dbnum++, new_dbnum++)
        {
-               DbInfo     *old_db = &old_db_arr->dbs[dbnum];
-               DbInfo     *new_db = &new_db_arr->dbs[dbnum];
+               DbInfo     *old_db = &old_db_arr->dbs[old_dbnum];
+               DbInfo     *new_db = &new_db_arr->dbs[new_dbnum];
                FileNameMap *mappings;
                int                     n_maps;
                pageCnvCtx *pageConverter = NULL;
 
+               /*
+                *      Advance past any databases that exist in the new cluster
+                *      but not in the old, e.g. "postgres".
+                */
+               while (strcmp(old_db->db_name, new_db->db_name) != 0 &&
+                          new_dbnum < new_db_arr->ndbs)
+                       new_db = &new_db_arr->dbs[++new_dbnum];
+
                if (strcmp(old_db->db_name, new_db->db_name) != 0)
                        pg_log(PG_FATAL, "old and new databases have different names: old \"%s\", new \"%s\"\n",
                                   old_db->db_name, new_db->db_name);