Not equal <> != operator on NULL

Question

Could someone please explain the following behavior in SQL?

SELECT * FROM MyTable WHERE MyColumn != NULL (0 Results)
SELECT * FROM MyTable WHERE MyColumn <         


        

Answer 1

NULL is not anything...it is unknown. NULL does not equal anything. That is why you have to use the magic phrase IS NULL instead of = NULL in your SQL queries

You can refer this: http://weblogs.sqlteam.com/markc/archive/2009/06/08/60929.aspx