mistake, error, or something else ?

Hi people.
I've this query:

select a,b,c from t1
where c in (select distinct c from t2);

this query run succesfully BUT:

select distinct c from t2
give me: ora-904 Invalid column name.

WHY ???? i've no synonym or other objects

t1 has 3 columns, a,b,c
t2 has 2 columns d,e

Tia

Mike Received on Mon Oct 27 2003 - 08:14:44 CST