Mysql中的并发事务

我有一个accounts表。帐户id 1的余额是550。假设mysql的一个连接正在这样做：

START TRANSACTION;
update accounts set balance = balance - 200 where id = 1 #TIME t 
update accounts set balance = balance + 200 where id = 2 #TIME t + 100  
COMMIT

START TRANSACTION;
update accounts set balance = balance - 100 where id = 1 and balance > 500 #TIME t  + 50 
COMMIT

现在假设另一个连接正在执行此操作：

START TRANSACTION;
update accounts set balance = balance - 200 where id = 1 #TIME t 
update accounts set balance = balance + 200 where id = 2 #TIME t + 100  
COMMIT

START TRANSACTION;
update accounts set balance = balance - 100 where id = 1 and balance > 500 #TIME t  + 50 
COMMIT

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我想知道数据库的最终状态是什么以及为什么？

这取决于事务隔离级别的类型。@助记符：谢谢！我觉得这个视频很有趣。