Question

如果你小心并且在所有事情上使用TRY-CATCH，并且你真的需要使用错误回滚：

SET XACT_ABORT ON

换句话说，是否有任何TRY-CATCH会错过SET XACT_ABORT ON会处理的错误？

Answer 1

请记住，TRY-CATCH无法使用或不使用XACT_ABORT进行捕获。

但是，SET XACT_ABORT ON不会影响错误的捕获。它确实保证任何事务都回滚/注定失败。当“关闭”时，您仍然可以选择提交或回滚（受xact_state约束）。这是SQL 2005对XACT_ABORT

的主要行为更改

如果客户端命令超时启动并且客户端发送“abort”指令，它还会删除锁等。如果没有SET XACT_ABORT，则在连接保持打开状态时可以保留锁定。我的同事（MVP）和我在今年年初对此进行了彻底的测试。

Answer 2

我认为执行分布式事务时需要SET XACT_ABORT ON。

From the books on line: 对于大多数OLE DB提供程序（包括SQL Server）的隐式或显式事务中的数据修改语句，必须将XACT_ABORT设置为ON。不需要此选项的唯一情况是提供程序是否支持嵌套事务。有关更多信息，请参阅分布式查询和分布式事务。

Answer 3

XACT_ABORT确实会影响错误处理：它会在遇到错误时中止整个批处理，并且产生错误的行后面的任何代码（包括错误检查！）将永远不会执行。此行为有两个例外：XACT_ABORT被TRY ... CATCH取代（CATCH块将始终执行，事务不会自动回滚，只能呈现不可承受），XACT_ABORT将忽略RAISERROR。

Answer 4

我的理解是，即使使用try catch并且在catch块中没有使用rollback语句，当XACT_ABORT为ON时，任何不可提交的事务都将被回滚。

Answer 5

盲目地总是使用SET XACT_ABORT ON;这最近烧了我。

我在StackOverflow上阅读了一个令人信服的论点，建议你总是使用XACT_ABORT ON。我更改了系统以在连接期间设置该选项。除了它导致数据损坏和许多痛苦。

begin transaction
try
    perform insert
    catch duplicate key violation and react appropriately

    perform more actions

    commit transaction
catch
    rollback transaction
end

除了您的“更多操作”将不再在交易中发生。因为即使您发现重复密钥违规，服务器也不再处于事务中：

begin transaction
try
    perform insert
    catch duplicate key violation and react appropriately
    transaction implicitly rolled back

    perform more actions

    commit transaction -> fails because not in a transaction
catch
    rollback transaction -> fails because not i a transaction
end

我已经扭转了自己。从不使用SET XACT_ABORT ON。

修改：人们似乎认为问题来自于尝试在不在交易中时调用ROLLBACK TRANSACTION。如果交易没有进行，他们认为可以通过不调用ROLLBACK来解决问题。

让我们使用一些伪代码，更改名称以保护NDA：

const
   SQLNativeErrorPrimaryKeyViolation = 2627; //Primary keys. 2601 is for other unique index

void x(String sql)
{
   database.Connection.ExecuteNoRecords(sql);
}

这是使这个答案更具可读性的迂腐方式;我们使用x来表示某些SQL语句的执行：

void DoStuff()
{
   x("BEGIN TRANSACTION");
   try
   {
      try
      {
         x("INSERT INTO Patrons (AccountNumber, Name, Gender)"+
           "VALUES (619, 'Shelby Jackson', 'W'"); 
      } 
      catch (ESqlServerException e)
      {
         //check if the patron already exists (or some other hypothetical situation arises)
         if (e.NativeError == SQLNativeErrorPrimaryKeyViolation)
         {
            //This patron already exists. Set their frob to grob because contoso the blingblong
            x("UPDATE Patrons SET Frob='Grob' WHERE AccountNumber = 619");

            //20110918: Dont forget we also need to bang the gardinker
            x("EXECUTE BangTheGardinker @floof=619");
         }
         else
            throw e;
      }

      //Continue with the stuff
      x("EXECUTE Frob('{498BBB4D-D9F7-4438-B7A6-4AB5D57937C0}')");

      //All done, commit the transaction
      x("COMMIT TRANSACTION");       
   }
   catch (Exception e)
   {
      //Something bad happened, rollback the transaction 
      //(if SQL Server didn't kill the transaction without our permission)
      x("IF @@TRANCOUNT > 0 ROLLBACK TRANSACTION");


      throw e;
   }
}

XACT_ABORT ON很酷，让我们用它

所以，该代码有效。如果我们期望出现错误，我们会处理并继续。这称为处理错误。如果发生了一些未知异常（我们没想到的话），我们rollback可能正在进行的任何交易。

现在让我们看看我们是否盲目遵循XACT_ABORT始终应该遵循的建议：

 DbConnection Connection()
 {
    if (_connection == null)
    {
       _connection = new SqlConnection();

       //It is generally recommended that you always have xact_abort on.
       //If a connection is closed with a transaction still in progress
       //it still leaves locks held until that connection is finally recycled
       //Also, when querying linked severs in a client-side transaction, the
       //operation won't work until xact_abort is on (SQL Server will throw an saying xactabort is off
       _connection.ExecuteNoRecords("SET XACT_ABORT ON");
    }

    return _connection;
 }

void x(String sql)
{
   database.Connection.ExecuteNoRecords(sql);
}

您是否看到 DoStuff 会导致损坏？

正确编写

DoStuff 以处理错误情况。但是，XACT_ABORT ON引入连接现在会导致数据库损坏。对于那些没有看到错误的人，让我们来看看代码：

void DoStuff()
{
   x("BEGIN TRANSACTION");
   try
   {
      try
      {
         x("INSERT INTO Patrons (AccountNumber, Name, Gender)"+
           "VALUES (619, 'Shelby Jackson', 'W'"); 

      } 
      catch (ESqlServerException e)
      {
         //WARNING: WE ARE NO LONGER OPERATING IN A TRANASCTION
         //Because XACT_ABORT is on, the transaction that we started has been implicitly rolled back.
         //From now on, we are no longer in a transaction. If another error happens
         //the changes we make cannot be rolled back

         //check if the patron already exists (or some other hypothetical situation arises)
         if (e.NativeError == SQLNativeErrorPrimaryKeyViolation)
         {
            //WARNING: This update happens outside of any transaction!
            //This patron already exist. Set their frob to grob because contoso the blingblong
            x("UPDATE Patrons SET Frob='Grob' WHERE AccountNumber = 619");

            //WARNING: This stored procedure happens outside of any transaction!
            //20110918: Dont forget we also need to bang the gardinker
            x("EXECUTE BangTheGardinker @floof=619");
         }
         else
            throw e;
      }

      //WARNING: This stored procedure happens outside of any transaction!
      //If any error happens from
      //Continue with the stuff
      x("EXECUTE Frob('{498BBB4D-D9F7-4438-B7A6-4AB5D57937C0}')");

      //WARNING: This stored procedure happens outside of any transaction. It will throw:
      //   Msg 3902, Level 16, State 1, Line 1
      //   The COMMIT TRANSACTION request has no corresponding BEGIN TRANSACTION.
      //All done, commit the transaction
      x("COMMIT TRANSACTION");       
   }
   catch (Exception e)
   {
      //If there was an error during Frob, we would want to catch it and roll everything back.
      //But since SQL Server ended the transaction, we have no way to rollback the changes

      //And even if the call to Frob (or Updating the patron's Grob, or Banging the Gardinder)
      //didn't fail, the call to COMMIT TRANSACTION will throw an error

      //Either way, we have detected an error condition that cannot be rolled back in the database


      //Something bad happened, rollback the transaction 
      //(if SQL Server didn't kill the transaction without our permission)
      x("IF @@TRANCOUNT > 0 ROLLBACK TRANSACTION");


      throw e;
   }
}

正确编写并且正常运行的代码会损坏，导致错误，最坏的情况会导致数据库损坏。所有这些都是因为我打开了XACT_ABORT ON。

Answer 6

当XACT_ABORT在触发器中设置为OFF并且我在触发器主体中调用RAISEERROR时，更改未回滚。

我真的需要使用“SET XACT_ABORT ON”吗？

6 个答案:

XACT_ABORT ON很酷，让我们用它

您是否看到 DoStuff 会导致损坏？