Bug#7241 - Invalid response when DELETE .. USING and LOCK TABLES used.

  Only acquire necessary write lock for multi-delete

mysql-test/r/lock.result

@@ -47,3 +47,13 @@ unlock tables;
 lock tables t1 write, t1 as t1_alias read;
 insert into t1 select index1,nr from t1 as t1_alias;
 drop table t1,t2;
+create table t1 ( a int(11) not null auto_increment, primary key(a));
+create table t2 ( a int(11) not null auto_increment, primary key(a));
+lock tables t1 write, t2 read;
+delete from t1 using t1,t2 where t1.a=t2.a;
+delete t1 from t1,t2 where t1.a=t2.a;
+delete from t2 using t1,t2 where t1.a=t2.a;
+ERROR HY000: Table 't2' was locked with a READ lock and can't be updated
+delete t2 from t1,t2 where t1.a=t2.a;
+ERROR HY000: Table 't2' was locked with a READ lock and can't be updated
+drop table t1,t2;

mysql-test/t/lock.test

@@ -59,3 +59,17 @@ unlock tables;
 lock tables t1 write, t1 as t1_alias read;
 insert into t1 select index1,nr from t1 as t1_alias;
 drop table t1,t2;
+
+#
+# Bug7241 - Invalid response when DELETE .. USING and LOCK TABLES used.
+#
+create table t1 ( a int(11) not null auto_increment, primary key(a));
+create table t2 ( a int(11) not null auto_increment, primary key(a));
+lock tables t1 write, t2 read;
+delete from t1 using t1,t2 where t1.a=t2.a;
+delete t1 from t1,t2 where t1.a=t2.a;
+--error 1099
+delete from t2 using t1,t2 where t1.a=t2.a;
+--error 1099
+delete t2 from t1,t2 where t1.a=t2.a;
+drop table t1,t2;

sql/sql_parse.cc

@@ -4141,6 +4141,7 @@ void mysql_init_multi_delete(LEX *lex)
   lex->select_lex.select_limit= lex->unit.select_limit_cnt=
     HA_POS_ERROR;
   lex->select_lex.table_list.save_and_clear(&lex->auxilliary_table_list);
+  lex->lock_option= using_update_log ? TL_READ_NO_INSERT : TL_READ;
 }
 
 
@@ -5437,6 +5438,11 @@ int multi_delete_precheck(THD *thd, TABLE_LIST *tables, uint *table_count)
     }
     walk->lock_type= target_tbl->lock_type;
     target_tbl->table_list= walk;	// Remember corresponding table
+    if (walk->table_list)
+    {
+      target_tbl->table_list= walk->table_list;
+      walk->table_list->lock_type= walk->lock_type;
+    }
   }
   DBUG_RETURN(0);
 }