java - Hibernate second level cache and RR transaction isolation

Question

If two transactions (both at RR isolation level) ask for the same item which is 2nd-level cached, and then they modify and store this item. Now, for reading that item, they did not run any SQL because it's cached; so in this case, will they actually start a data base transaction? And when they commit their changes, will they run into lost update problem?

Answer 1

从悲观的角度来看：

如果二级缓存被配置为参与事务，那么只有第一个获得写锁的缓存才能修改缓存对象，然后将更改写入数据库。当第二个事务想要获取写锁时，它必须等到第一个事务结束并释放它。

使用乐观锁定，我猜应该会发生并发修改异常（或类似名称），并且第二个事务将重试操作。