Hi everyone,
This is my first post... I had to do it.
Lets say I got two tables:
1) Autors
2) Books
you can keep autors' data even if they haven't written any book. My question is how do I find them?
I already got subset of autors that have written one and a set of all existing autors. Now I need to get difference between those two sets right? Can ya help me?
Thnx v. much

select author_id from authors
minus
select author_id from books

... assuming your DBMS supports MINUS (or possibly EXCEPT, which is the same thing)

Rite,
I forgot to mention the most important thing - its MS SQL SRV and from what I know it doesnt support MINUS or EXCEPT

In that case you could use NOT EXISTS...

select * from authors where not exists (select 1 from books where books.author_id = authors.author_id);