SQL Server transaction and rollback

If you have to be careful when you want to perform data churn in production, you can use transactions to verify in advance whether your own SQL is what you expect. Especially if there is a problem with the where condition of the update, the new record will exceed the expected range. As the following statement, a hurry I almost put cartid = 678417 Forget, if in production implementation impact is big.

BEGIN TRANSACTIONUpdateCartitemSetDeleted=0 whereCartid= 678417  andModifiedDate> '2014-08-07'Select *  fromCartitemwhereCartid= 678417 Order  byModifiedDatedescROLLBACK TRANSACTION

The following statement implements the statement between Begin Tran and commit Tran, either if an error occurs,

 set  xact_abort on  -- -if the key is not set to ON, the default is off in SQL, then only the Transact-SQL statement that generated the error is rolled back; set to on to roll back the entire transaction  begin  tran  t1 -- -start a transaction  update  Cartitem set  deleted=  0  where  cartid =  Span style= "font-weight:bold; Color: #800000 ">678417  and  modifieddate    " 2014-08-07  "  

Commit Tran T1  ---commit a transaction

Try, Catch for a transaction

BEGINTRYBEGIN TRANSACTION     Insert  intoDbo.areaValues('1111')    Insert  intoDbo.areaValues('2222')    Select 1/0    Insert  intoDbo.areaValues('333')   COMMITENDTRYBEGINCATCHIF @ @TRANCOUNT > 0     ROLLBACK  DECLARE @ErrMsg nvarchar(4000),@ErrSeverity int  SELECT @ErrMsg =error_message (),@ErrSeverity =error_severity ()RAISERROR(@ErrMsg,@ErrSeverity,1)ENDCatch