How to resolve the ORA-00031 (session marked for kill)

* select
spid,
osuser,
s.program
from v$process p,
v$session s
where p.addr=s.paddr and osuser = 'user_name'
/

 you will fetch the spid to be killed through Operating system promt

In Linux  through kill -9  command kill the process fetched from the above query.

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