Thanks to all the EXEPT keyword is what I was looking for On Thu, May 22, 2008 at 5:36 PM, Niklas Johansson <[EMAIL PROTECTED]> wrote:
> > On 22 maj 2008, at 17.15, Nacef LABIDI wrote: > >> I was wondering how can I substract result between select queries. I mean >> I want to issue a query that does this : >> (select * from mytable where condition1) - (select * from mytable where >> condition2) >> > > If you (as implied above) query the same table in both cases, just do: > > SELECT * FROM mytable WHERE condition1 AND NOT condition2 > > Otherwise, use EXCEPT: > > SELECT * FROM mytable1 WHERE condition1 > EXCEPT > SELECT * FROM mytable2 WHERE condition2 > > in which case both queries must return the same type of rows. > > > > > Sincerely, > > Niklas Johansson > > > >
