首页  流程图  详情

Transaction

2019-08-26 10:28:14   0  举报





仅支持查看

为你推荐

查看更多



SQL

作者其他创作

大纲/内容

UPDATE account SET balance = 1700 WHERE account_id = 1;

SELECT * FROM account;+----+------------+---------+| id | account_id | balance |+----+------------+---------+| 1 | 1 | 1700 || 4 | 2 | 1800 |+----+------------+---------+

Time Line

Transaction A\"Transfer 500 from 1 to 2\"

locked

blocking

SELECT * FROM account;+----+------------+---------+| id | account_id | balance |+----+------------+---------+| 1 | 1 | 1000 || 4 | 2 | 2000 |+----+------------+---------+

lock account_id 1

Transaction B\"Transfer 200 from 2 to 1\"

UPDATE account SET balance = 2500 WHERE account_id = 2;

START TRANSACTION;

UPDATE account SET balance = 1000 WHERE account_id = 1;

SELECT * FROM account;+----+------------+---------+| id | account_id | balance |+----+------------+---------+| 1 | 1 | 1000 || 4 | 2 | 2500 |+----+------------+---------+

SELECT * FROM account;+----+------------+---------+| id | account_id | balance |+----+------------+---------+| 1 | 1 | 1500 || 4 | 2 | 2000 |+----+------------+---------+

COMMIT;

unlock all

UPDATE account SET balance = 1800 WHERE account_id = 2;

SELECT * FROM account;+----+------------+---------+| id | account_id | balance |+----+------------+---------+| 1 | 1 | 1700 || 4 | 2 | 1800 |+----+------------+---------+