what Sqls/scripts/modules are running in the databases by what users?

Solution: Use the following script

column username format a15 word_wrapped
column module format a15 word_wrapped
column action format a15 word_wrapped
column client_info format a30 word_wrapped

select username'('sid','serial#')' username, module, action, client_infofrom v$sessionwhere moduleactionclient_info is not null;