[20131014] 出现错误,显示事务没有回滚 测试代码: TRY DELETE dbo.T TRY BEGIN CATCH CATCH COMMIT /* 问题:1.SELECT * FROM [不存在的表] 为什么会直接跳出,不完成事务?2.SELECT * FROM [不存在的表] 是否属于编译错误?3.修改为SET XACT_ABORT ON 可以回
[20131014] 出现错误,显示事务没有回滚
测试代码:
TRY DELETE dbo.T TRY BEGIN CATCH CATCH COMMIT /*问题: 1.SELECT * FROM [不存在的表] 为什么会直接跳出,不完成事务? 2.SELECT * FROM [不存在的表] 是否属于编译错误? 3.修改为SET XACT_ABORT ON 可以回滚,如果SELECT * FROM [不存在的表]是编译错误 那么联机文档中:编译错误(如语法错误)不受 SET XACT_ABORT 的影响。如何解释? */
问题:
在一个session中运行以上代码,然后在另外一个session运行 select * from T,发现select语句被堵塞
原因:
sql 编译的流程 Parse->Bind->Optimize->Execute
一般认为从Parse到Optimize 是编译阶段,,Execute是执行阶段
猜测try catch不会再Bind和Optimize阶段出现的错误进行捕获,以上出现的错误可能不被认为是编译错误,所以,使用 xact 为on是可以成功自动回滚
解决方法:
使用 SET XACT_ABORT ON 来回滚事物
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