Query that returns 2 different results in 9iRAC and 10gRac

Try this query on 9iRac and 10gRac, it returns 2 differnet results.

with qw as (select inst_id from gv$session), y as (

   select unique inst_id
     from qw
   union all
   select unique inst_id
    from qw
  )

I logged a tar and was told this is not a bug. The explanation made no sense whatsoever. Received on Wed Mar 09 2005 - 14:58:44 CST