SQL query to not to exclude NULLS

Question

Hi,
I have a column in table
Type
ABC
XYZ
     -- NULL
     -- NULLWhen I write sql statement to exclude Type = 'ABC', the query also excluding NULLs. How to avoid (include nulls) that?

Answer 1

...or (this is not the best one):
select * from yourtable
WHERE nvl2(type,type,'?') != 'ABC'
select * from yourtable
WHERE decode(type,null,'?',type) != 'ABC'..it's only for 'educational' purpose (an excuse to show the nvl2 and decode functions)
or
    select * from yourtable
    where coalesce(type,'?')!= 'ABC'sorry i stop here now.
select * from yourtable
    where nullif(type,'ABC')= type or type is nullEdited by: user11268895 on Aug 31, 2010 5:10 PM