5. Example. SQL functions.sql

SELECT ISNULL(CONVERT(VARCHAR(MAX), ord.OrderDate), 'Sin Fecha')
FROM [ORDER] ord;
GO

/** Output **/
--------------------
Jul  4 2012 12:00AM
Jul  5 2012 12:00AM
Jul  8 2012 12:00AM
Jul  8 2012 12:00AM
Jul  9 2012 12:00AM
Jul 10 2012 12:00AM
Jul 11 2012 12:00AM
Jul 12 2012 12:00AM
...

SELECT NULLIF(100, 50*2);
GO

/** Output **/
----
NULL

SELECT NULLIF(2*2, 2*7);
GO

/** Output **/
-----------
4

SELECT COALESCE(sup.Phone, sup.Fax) "Contacto"
FROM Supplier sup;
GO

/** Output **/
Contacto
------------------------------
(171) 555-2222
(100) 555-4822
(313) 555-5735
(03) 3555-5011
(98) 598 76 54
...