SQL Server 2008 Transactions Usage Template

I must admit I don't use Transactions that much, but the fact is that most of my stored procedures are atomic, i.e. although they may have a lot of code, only one data changing operation (INSERT | UPDATE | DELETE) is done, so there's no need to wrap it on a transaction.

Because I don't use them much, its not always clear to me what's the "best way" of using a transaction. Sure we all know the basics but:

• Is the transaction always closed?
• Are we handling the error that caused the transaction to rollback?
• Are we accurately reporting the error to the caller?

To be able to always answer YES to all these questions without thinking much about it, my friend Rui Inacio dove into Google and came up with a template that can be used as a start point of all your transaction scripts.

BEGIN TRY
 BEGIN TRANSACTION

  -- ADD YOUR CODE HERE --

 IF @@TRANCOUNT > 0
 BEGIN
  COMMIT TRANSACTION;
 END
END TRY
BEGIN CATCH
 DECLARE @ErrorMessage VARCHAR(4000)

 SET @ErrorMessage = 'ErrorProcedure: ' + ISNULL(ERROR_PROCEDURE(), '') + ' Line: ' + CAST(ERROR_LINE() AS VARCHAR(10)) + ' Message: ' + ERROR_MESSAGE()

 IF @@TRANCOUNT > 0
 BEGIN
  ROLLBACK TRANSACTION;
 END

 RAISERROR (@ErrorMessage, 16, 1)
END CATCH

You may change the way you report the error inside the CATCH but for most cases this is what you need.