How to Identify SID Based on OS PID in Oracle

How to Identify SID Based on OS PID in Oracle

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Query to check SID from PID (get from top command )

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set lines 200 pages 500

col sid format 99999
col username format a30
col osuser format a15
select p.spid,s.sid, s.serial#,s.username, s.osuser
from gv$session s, gv$process p
where s.paddr= p.addr
and p.spid='&spid'

order by p.spid;