SQL & PL/SQL

Hi,

I need to identify single rows of a given (say "query1") query which may occur several times nested in another query. E.g. like this:

select * from (<query1>) T join (<query1>) S on ...

Now, if I select ROWNUM in "query1" will the selction order be the same every time (i.e. will the same rows have the same rownum in every occurence of "query1"?).

I want to be able to do something like:

select * from (<query1>) T join (<query1>) S using (rownum)

and corresponding tuples to be matched.
(Ok, basically the query above won't work, I'll have to use an alias for "rownum" in "query1" and join on that, but you get the idea.)

Thanks,
Al