How to see active session in Oracle

Check active session in Oracle


 SELECT NVL(s.username, '(oracle)') "USERNAME",
       s.osuser "OSUSER",
       s.sid "SID",
       s.serial# "SERIAL#",
       p.spid "SPID",
       s.lockwait "LOCKWAIT",
       s.status "STATUS",
       s.module "MODULE",
       s.machine "MACHINE",
       s.program "PROGRAM",
       s.sql_hash_value "HASH",
       TO_CHAR(s.logon_Time,'DD-MON-YYYY HH24:MI:SS') "LOGONTIME"
FROM   v$session s,
       v$process p
WHERE  s.paddr  = p.addr
AND    s.status = 'ACTIVE'
ORDER BY s.username, s.osuser;