在SQL Server的try...catch语句中获取错误消息的代码

BEGIN TRY
    ...
    ...
END TRY
BEGIN CATCH
    DECLARE @ErrorMessage NVARCHAR(4000);
    DECLARE @ErrorSeverity INT;
    DECLARE @ErrorState INT;

    SELECT 
        @ErrorMessage = ERROR_MESSAGE(),
        @ErrorSeverity = ERROR_SEVERITY(),
        @ErrorState = ERROR_STATE();

    RAISERROR (@ErrorMessage,  -- Message text.
               @ErrorSeverity, -- Severity.
               @ErrorState     -- State.
               );
END CATCH;