MySQL忽然出现某些记录无法更新
MySQL突然出现某些记录无法更新 ??? 一直运行良好的系统这两天出现奇怪的问题:某些记录无法更新成功。具体错误如下: ?Caused by: org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; e
MySQL突然出现某些记录无法更新??? 一直运行良好的系统这两天出现奇怪的问题:某些记录无法更新成功。具体错误如下:
?Caused by: org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1
??????? at org.hibernate.jdbc.Expectations$BasicExpectation.checkBatched(Expectations.java:85)
??????? at org.hibernate.jdbc.Expectations$BasicExpectation.verifyOutcome(Expectations.java:70)
??????? at org.hibernate.jdbc.BatchingBatcher.checkRowCounts(BatchingBatcher.java:90)
??????? at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
??????? at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)
??????? at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:268)
??????? at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:185)
??????? at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
??????? at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51)
??????? at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
??????? at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383)
??????? at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133)
考虑到这两天系统只是前端有少许改动,于是让前端开发人员去定位,前端定位半天后说相关地方没改动,要求后台开发人员查,后台开发人员很抗拒,因为最近后台并没更新,这问题是这两天才出现的,后台不情愿地追踪了半天蒙了,发现同样的代码流程,某些记录能够更新成功,某些则失败。后台直接跟我说搞不定了,太诡异了。无奈之下只好自己去查。
?
??? 网上搜到的关于Caused by: org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1 异常的文章都和我们的情况不符。该异常的描述的意思是:本次更新本来期望能得到更行成功一条的返回信息,却得到成功0条,于是hibernate就报错了。
?
??? 根据反复的测试和debug,发现几个特点:1. 可以更新的记录总是可以更新;2. 更新失败的总是更新失败;3. 新增的记录总是可以更新成功;4. 可以更新的和不可以更新的记录间找不出规律能将两类区分;5. (最重要的一点)不能更新的记录手动也无法更新。
???
??? 上面的第5点让我想起本周虚拟机挂掉的情况,我们的系统都跑在虚拟机上,本周一所有的虚拟机都挂掉了,后来由维护人员恢复了。难道这次宕机让硬盘受到损害导致MySQL部分数据只能读无法写?为了验证这个想法,我把数据库全部导出然后再全部导入,问题解决了!
?
???? 这真是个有趣的问题,什么样的损害会导致MySQL只能读取一条记录但是无法修改它呢?

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