Replacing @@ERROR Based Error Handling With Structured Exception Handling

Question

Could please any one explain 
Thanks

Answer 1

Hi Rmohan,
In SQL Server 2008 R2, we can use RAISERROR to generate an error message and initiates error processing for the session. RAISERROR can either reference a user-defined message stored in the sys.messages catalog view or build a message dynamically.
Do you want to build a custom error message? If so, you can use the following script:
Begin Try
RAISERROR ('Generate custom error message.', -- Message text.
16, -- Severity.
1 -- State.
End Try
Begin Catch
-- We can also print the error message if necessary
Print 'custom error message'
DECLARE @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 jump to the CATCH block.
RAISERROR (@ErrorMessage, -- Message text.
@ErrorSeverity, -- Severity.
@ErrorState -- State.
End Catch
The result is as follows:
Reference:
http://msdn.microsoft.com/en-IN/library/ms178592(v=sql.105).aspx
Regards,
Mike Yin
TechNet Community Support