What's the process or the user doing?

[tamilselvan]

Yes. You can see the running SQL statement from the following statement:

select a.osuser, c.spid, a.username, a.sid, a.status,
a.program, b.sql_text
from v$session a, v$sqltext_with_newlines b, v$process c
where a.sql_address = b.address
and a.sql_hash_value = b.hash_value
and a.type != 'BACKGROUND'
and a.paddr = c.addr
order by a.status, a.osuser, a.username, a.sid, b.piece ;