querying null columns

[aneev]

I have a query in which I need to find all the rows with a specific column being null.
Ex:
select count(*) from proposal_review_info where reviewerid='xyz' and status=1 and review_result='';
the above query does not work. What is the correct solution for the above query?

 

[stoolpigeon]

Null is not a value- it is the lack of a value. So you can't check to see if something equals null. Nothing equals null by definition. You need to use the IS NULL condition.

select count(*) from  proposal_review_info where reviewerid='xyz' and status=1 and review_result is null;