Re: How to retrieve rows with empty value in numeric(12,8) columns

On 06/12/2011 11:00, Adarsh Sharma wrote:
> try
>>
>> select * from table where lat IS NULL;
>>
>> Bèrto
> :-) It works, Thanks a lot Berto !
>
> can you explain how it works or any link that explain the difference
> between 2 queries.

As I understand it, your first query returned nothing because NULL is
simply "unknown" - and since you can never know what it's equal to,
looking for equality with NULL will never find anything.

Ray.

--
Raymond O'Donnell :: Galway :: Ireland
rod@iol.ie