Bug #21392: multi-table delete with alias table name fails with

            1003: Incorrect table name
in multi-table DELETE the set of tables to delete from actually 
references then tables in the other list, e.g:
DELETE alias_of_t1 FROM t1 alias_of_t1 WHERE ....
is a valid statement.
So we must turn off table name syntactical validity check for alias_of_t1 
because it's not a table name (even if it looks like one).
In order to do that we add a special flag (TL_OPTION_ALIAS) to 
disable the name checking for the aliases in multi-table DELETE.


mysql-test/r/delete.result:
  Bug #21392: multi-table delete with alias table name fails with
              1003: Incorrect table name
   - test case
mysql-test/t/delete.test:
  Bug #21392: multi-table delete with alias table name fails with
              1003: Incorrect table name
   - test case
sql/mysql_priv.h:
  Bug #21392: multi-table delete with alias table name fails with
              1003: Incorrect table name
   - add a special flag to disable the name checking for the aliases
     in multi-table DELETE
sql/sql_parse.cc:
  Bug #21392: multi-table delete with alias table name fails with
              1003: Incorrect table name
   - add a special flag to disable the name checking for the aliases
     in multi-table DELETE
sql/sql_yacc.yy:
  Bug #21392: multi-table delete with alias table name fails with
              1003: Incorrect table name
   - add a special flag to disable the name checking for the aliases
     in multi-table DELETE

1 files changed, 3 insertions, 1 deletions

diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index cf1f50aed63..c84c96e1e75 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -4863,6 +4863,7 @@ bool add_to_list(THD *thd, SQL_LIST &list,Item *item,bool asc)
     table_options	A set of the following bits:
 			TL_OPTION_UPDATING	Table will be updated
 			TL_OPTION_FORCE_INDEX	Force usage of index
+			TL_OPTION_ALIAS	        an alias in multi table DELETE
     lock_type		How table should be locked
     use_index		List of indexed used in USE INDEX
     ignore_index	List of indexed used in IGNORE INDEX
@@ -4888,7 +4889,8 @@ TABLE_LIST *st_select_lex::add_table_to_list(THD *thd,
   if (!table)
     DBUG_RETURN(0);				// End of memory
   alias_str= alias ? alias->str : table->table.str;
-  if (check_table_name(table->table.str,table->table.length) ||
+  if (!test(table_options & TL_OPTION_ALIAS) &&
+       check_table_name(table->table.str,table->table.length) ||
       table->db.str && check_db_name(table->db.str))
   {
     net_printf(thd, ER_WRONG_TABLE_NAME, table->table.str);