SQL Server - Try, Catch and Throw Exception

Wasn't sure until now how to re-throw a caught error in SQL Server - turns out it's relatively straightforward using RAISERROR:

BEGIN TRY
    -- RAISERROR with severity 11-19 will cause execution to
    -- jump to the CATCH block.
    RAISERROR ('Error raised in TRY block.', -- Message text.
               16, -- Severity.
               1 -- State.
               );
END TRY
BEGIN CATCH
    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;

Source: http://msdn.microsoft.com/en-us/library/ms178592.aspx