When writing SQL procedures, it is really important to handle errors cautiously. Having that in mind will probably save your efforts, time and money. I have been working with MS-SQL 2000 and MS-SQL 2005 (I have not got the opportunity to work with MS-SQL 2008 yet) for many years now and I want to share with you how I handle errors in T-SQL Stored Procedure. This code has been working for many years now without a hitch.
N.B.: As antoher "best pratice", I suggest using only ONE level of TRY … CATCH and only ONE level of TRANSACTION encapsulation, as doing otherwise may not be 100% sure.
BEGIN TRANSACTION;
BEGIN TRY
-- Code in transaction go here
COMMIT TRANSACTION;
END TRY BEGIN CATCH
-- Rollback on error
ROLLBACK TRANSACTION;
-- Raise the error with the appropriate message and error severity
DECLARE @ErrMsg nvarchar(4000), @ErrSeverity int;
SELECT @ErrMsg = ERROR_MESSAGE(), @ErrSeverity = ERROR_SEVERITY();
RAISERROR(@ErrMsg, @ErrSeverity, 1);
END CATCH;
In conclusion, I will just mention that I have been using this code with .NET 2.0 and .NET 3.5 and it works like a charm. The .NET TDS parser throws back a SQLException which is ideal to work with.
