← Sequences – where did the view go?
so how does that work if you open a Dataguard database read only? You are writing into sys.aud$ on the Primary, and that table is replicated to the Standby. So what happens?
So it starts writing down O/S audit trail files for all of your auditing options (well, the session connect and DML audit options – you can’t run DDL in a r/o DB). You might want to go and see just how many files it has written to [audit_file_dest], as you may be surprised at just how many are in there.
You may, one day, either run out of space or (more worryingly) have so many millions of files that it causes a performance problem when Oracle access the O/S directory. You might want to think about some sort of periodic clean-up job.