Oracle DBA scripts - Session related

1. Find my ORACLE SID
echo $ORACLE_SID
or,    less .profile 


2. Find my SID

SELECT sys_context('USERENV','SID') from dual;

3. Find others SID

SELECT a.sid,a.serial#,b.spid,b.pid,a.username,a.osuser,a.machine
FROM v$session a,v$process b
WHERE a.username IS NOT NULL
AND a.paddr=b.addr
Order by a.sid,a.username;

4. Find connected session,login_time in a given time

SELECT a.sid,a.serial#,a.username,a.osuser,a.machine,a.service_name
,to_char(a.logon_time, 'hh24:mi dd/mm/yy') login_time
FROM v$session a,v$process b
WHERE a.username IS NOT NULL
AND a.paddr=b.addr AND a.type='USER'
--AND a.logon_time> = sysdate- 1/48 --last 30 min
AND a.logon_time > to_date ('2008-10-18 15:00:00','YYYY-MM-DD HH24:MI:SS')
AND a.logon_time <> to_date ('2008-10-18 15:00:00','YYYY-MM-DD HH24:MI:SS')
Order by a.sid,a.username;