Updated on 2024-04-28 GMT+08:00

LOCK

DSC will perform adaptation based on GaussDB(DWS) features during the migration of MySQL table locking statements which are used in transaction processing.

Input

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
## A.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` WRITE,`mt`.`runoob_tb2` READ;
commit;

## B.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` WRITE;
commit;

## C.
START TRANSACTION;
LOCK TABLES `mt`.`runoob_tbl` READ,`mt`.`runoob_tbl` AS t1 READ;
commit;

Output

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
-- A.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS EXCLUSIVE MODE;
LOCK TABLE "mt"."runoob_tb2" IN ACCESS SHARE MODE;
COMMIT WORK;

-- B.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS EXCLUSIVE MODE;
COMMIT WORK;

-- C.
START TRANSACTION;
LOCK TABLE "mt"."runoob_tbl" IN ACCESS SHARE MODE;
COMMIT WORK;