SQL Server exception capture, rollback, and then throw

Multiple update operations in a stored procedure, followed by an exception to the update operation, if you do not manually rollback the previously modified data is not automatically revoked!

BEGINTRYBEGIN TRAN-- .....    COMMIT TRANENDTRYBEGINCATCHROLLBACK TRAN    DECLARE @ErrorMessag NVARCHAR(255)    SELECT @ErrorMessag =error_message ()RAISERROR(15600,-1,-1,@ErrorMessag);ENDCatch

Another reference: http://msdn.microsoft.com/zh-cn/library/ms178592.aspx

BEGINTRY--RAISERROR with severity 11-19 would cause execution to    --Jump to the CATCH block.    RAISERROR('Error raised in TRY block.',--Message text.                -,--Severity.               1 --State .               );ENDTRYBEGINCATCHDECLARE @ErrorMessage NVARCHAR(4000); DECLARE @ErrorSeverity INT; DECLARE @ErrorState INT; SELECT         @ErrorMessage =error_message (),@ErrorSeverity =error_severity (),@ErrorState =error_state (); --Use RAISERROR inside the CATCH block to return error    --information about the original error that caused    --execution to the CATCH block.    RAISERROR(@ErrorMessage,--Message text.               @ErrorSeverity,--Severity.               @ErrorState --State .               );ENDCATCH;

SQL Server exception capture, rollback, and then throw