DB2 sql: where clausole : something OR (table is empty)

I would like to have
a condition where in which I test if an element is present
in a tableX OR the tableX is empty.
The where will return true if the element is present in tableX
BUT return true even if the tableX is empty.
How do I do?
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

bobdylan75Author Commented:
select * from tableA
where tableA.key in (select key from tableX) OR tableX is empty...

Is there a way like that..
Kent OlsenDBACommented:

Hi Bob,

WHERE tableA.key in (select key from tableX)
  OR ((Select count(*) from tablex) = 0)

Will that work?


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Try using an outer join against the table that might have null or no value ?
bobdylan75Author Commented:
Thank you CarlsbergFTW,
but I think the easy way is that one of Kdo.
bobdylan75Author Commented:
thank you!
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.