Bug#14959: ALTER TABLE isn't able to rename a view

The mysql_alter_table() was able to rename only a table.

The view/table renaming code is moved from the function rename_tables 
to the new function called do_rename().
The mysql_alter_table() function calls it when it needs to rename a view.


mysql-test/t/rename.test:
  Added a test case for bug#14959: ALTER TABLE isn't able to rename a view
mysql-test/r/rename.result:
  Added a test case for bug#14959: ALTER TABLE isn't able to rename a view
sql/mysql_priv.h:
  Bug#14959: ALTER TABLE isn't able to rename a view
  Added the prototype of the do_rename() function.
sql/sql_rename.cc:
  Bug#14959: ALTER TABLE isn't able to rename a view
  The view/table renaming code is moved from the function rename_tables
  to the new function called do_rename().
sql/sql_table.cc:
  Bug#14959: ALTER TABLE isn't able to rename a view
  Added handling of a view rename to the mysql_alter_table() function.

mysql-test/r/rename.result

@@ -54,3 +54,13 @@ Tables_in_test
 t2
 t4
 drop table t2, t4;
+create table t1(f1 int);
+create view v1 as select * from t1;
+alter table v1 rename to v2;
+alter table v1 rename to v2;
+ERROR 42S02: Table 'test.v1' doesn't exist
+rename table v2 to v1;
+rename table v2 to v1;
+ERROR 42S01: Table 'v1' already exists
+drop view v1;
+drop table t1;

mysql-test/t/rename.test

@@ -72,4 +72,17 @@ disconnect con2;
 disconnect con1;
 connection default;
 
+#
+# Bug#14959: ALTER TABLE isn't able to rename a view
+#
+create table t1(f1 int);
+create view v1 as select * from t1;
+alter table v1 rename to v2;
+--error 1146
+alter table v1 rename to v2;
+rename table v2 to v1;
+--error 1050
+rename table v2 to v1;
+drop view v1;
+drop table t1;
 # End of 4.1 tests

sql/mysql_priv.h

@@ -648,6 +648,9 @@ int quick_rm_table(enum db_type base,const char *db,
 		   const char *table_name);
 void close_cached_table(THD *thd, TABLE *table);
 bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list);
+bool do_rename(THD *thd, TABLE_LIST *ren_table, char *new_db,
+                      char *new_table_name, char *new_table_alias,
+                      bool skip_error);
 bool mysql_change_db(THD *thd,const char *name,bool no_access_check);
 void mysql_parse(THD *thd,char *inBuf,uint length);
 bool mysql_test_parse_for_slave(THD *thd,char *inBuf,uint length);

sql/sql_rename.cc

@@ -126,38 +126,49 @@ static TABLE_LIST *reverse_table_list(TABLE_LIST *table_list)
 
 
 /*
-  Rename all tables in list; Return pointer to wrong entry if something goes
-  wrong.  Note that the table_list may be empty!
-*/
+  Rename a single table or a view
 
-static TABLE_LIST *
-rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
-{
-  TABLE_LIST *ren_table,*new_table;
-  frm_type_enum frm_type;
-  db_type table_type;
+  SYNPOSIS
+    do_rename()
+      thd               Thread handle
+      ren_table         A table/view to be renamed
+      new_db            The database to which the table to be moved to
+      new_table_name    The new table/view name
+      new_table_alias   The new table/view alias
+      skip_error        Whether to skip error
 
-  DBUG_ENTER("rename_tables");
+  DESCRIPTION
+    Rename a single table or a view.
 
-  for (ren_table= table_list; ren_table; ren_table= new_table->next_local)
-  {
+  RETURN
+    false     Ok
+    true      rename failed
+*/
+
+bool
+do_rename(THD *thd, TABLE_LIST *ren_table, char *new_db, char *new_table_name,
+          char *new_table_alias, bool skip_error)
+{
   int rc= 1;
   char name[FN_REFLEN];
   const char *new_alias, *old_alias;
+  frm_type_enum frm_type;
+  db_type table_type;
+
+  DBUG_ENTER("do_rename");
 
-    new_table= ren_table->next_local;
   if (lower_case_table_names == 2)
   {
     old_alias= ren_table->alias;
-      new_alias= new_table->alias;
+    new_alias= new_table_alias;
   }
   else
   {
     old_alias= ren_table->table_name;
-      new_alias= new_table->table_name;
+    new_alias= new_table_name;
   }
   sprintf(name,"%s/%s/%s%s",mysql_data_home,
-	    new_table->db, new_alias, reg_ext);
+          new_db, new_alias, reg_ext);
   unpack_filename(name, name);
   if (!access(name,F_OK))
   {
@@ -179,11 +190,11 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
       else
       {
         if (!(rc= mysql_rename_table(table_type, ren_table->db, old_alias,
-                                       new_table->db, new_alias)))
+                                     new_db, new_alias)))
         {
           if ((rc= Table_triggers_list::change_table_name(thd, ren_table->db,
                                                           old_alias,
-                                                            new_table->db,
+                                                          new_db,
                                                           new_alias)))
           {
             /*
@@ -192,7 +203,7 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
               triggers appropriately. So let us revert operations on .frm
               and handler's data and report about failure to rename table.
             */
-              (void) mysql_rename_table(table_type, new_table->db, new_alias,
+            (void) mysql_rename_table(table_type, new_db, new_alias,
                                       ren_table->db, old_alias);
           }
         }
@@ -201,9 +212,9 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
     }
     case FRMTYPE_VIEW:
       /* change of schema is not allowed */
-        if (strcmp(ren_table->db, new_table->db))
+      if (strcmp(ren_table->db, new_db))
         my_error(ER_FORBID_SCHEMA_CHANGE, MYF(0), ren_table->db, 
-                   new_table->db);
+                 new_db);
       else
         rc= mysql_rename_view(thd, new_alias, ren_table);
       break;
@@ -214,6 +225,47 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
       break;
   }
   if (rc && !skip_error)
+    DBUG_RETURN(1);
+
+  DBUG_RETURN(0);
+
+}
+/*
+  Rename all tables in list; Return pointer to wrong entry if something goes
+  wrong.  Note that the table_list may be empty!
+*/
+
+/*
+  Rename tables/views in the list
+
+  SYNPOSIS
+    rename_tables()
+      thd               Thread handle
+      table_list        List of tables to rename
+      skip_error        Whether to skip errors
+
+  DESCRIPTION
+    Take a table/view name from and odd list element and rename it to a
+    the name taken from list element+1. Note that the table_list may be
+    empty.
+
+  RETURN
+    false     Ok
+    true      rename failed
+*/
+
+static TABLE_LIST *
+rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
+{
+  TABLE_LIST *ren_table,*new_table, *tmp_table;
+
+  DBUG_ENTER("rename_tables");
+
+  for (ren_table= table_list; ren_table; ren_table= new_table->next_local)
+  {
+    new_table= ren_table->next_local;
+    if (do_rename(thd, ren_table, new_table->db, new_table->table_name,
+                  new_table->alias, skip_error))
       DBUG_RETURN(ren_table);
   }
   DBUG_RETURN(0);

sql/sql_table.cc

@@ -3154,9 +3154,10 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
   ha_rows copied,deleted;
   ulonglong next_insert_id;
   uint db_create_options, used_fields;
-  enum db_type old_db_type,new_db_type;
+  enum db_type old_db_type, new_db_type, table_type;
   bool need_copy_table;
   bool no_table_reopen= FALSE, varchar= FALSE;
+  frm_type_enum frm_type;
   DBUG_ENTER("mysql_alter_table");
 
   thd->proc_info="init";
@@ -3174,6 +3175,51 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
   if (alter_info->tablespace_op != NO_TABLESPACE_OP)
     DBUG_RETURN(mysql_discard_or_import_tablespace(thd,table_list,
 						   alter_info->tablespace_op));
+  sprintf(new_name_buff,"%s/%s/%s%s",mysql_data_home, db, table_name, reg_ext);
+  unpack_filename(new_name_buff, new_name_buff);
+  if (lower_case_table_names != 2)
+    my_casedn_str(files_charset_info, new_name_buff);
+  frm_type= mysql_frm_type(thd, new_name_buff, &table_type);
+  /* Rename a view */
+  if (frm_type == FRMTYPE_VIEW && !(alter_info->flags & ~ALTER_RENAME))
+  {
+    /*
+      Avoid problems with a rename on a table that we have locked or
+      if the user is trying to to do this in a transcation context
+    */
+
+    if (thd->locked_tables || thd->active_transaction())
+    {
+      my_message(ER_LOCK_OR_ACTIVE_TRANSACTION,
+                 ER(ER_LOCK_OR_ACTIVE_TRANSACTION), MYF(0));
+      DBUG_RETURN(1);
+    }
+
+    if (wait_if_global_read_lock(thd,0,1))
+      DBUG_RETURN(1);
+    VOID(pthread_mutex_lock(&LOCK_open));
+    if (lock_table_names(thd, table_list))
+      goto view_err;
+    
+    error=0;
+    if (!do_rename(thd, table_list, new_db, new_name, new_name, 1))
+    {
+      if (mysql_bin_log.is_open())
+      {
+        thd->clear_error();
+        Query_log_event qinfo(thd, thd->query, thd->query_length, 0, FALSE);
+        mysql_bin_log.write(&qinfo);
+      }
+      send_ok(thd);
+    }
+
+    unlock_table_names(thd, table_list, (TABLE_LIST*) 0);
+
+view_err:
+    pthread_mutex_unlock(&LOCK_open);
+    start_waiting_global_read_lock(thd);
+    DBUG_RETURN(error);
+  }
   if (!(table=open_ltable(thd,table_list,TL_WRITE_ALLOW_READ)))
     DBUG_RETURN(TRUE);