Killing the blocking session

Killing the blocking session
===============================

Normally, you should use the KILL USER SESSION menu found in TopSessions.
You can also issue an ALTER SESSION KILL SESSION sid, serial#; in an sqlplus
session.

When on unix or vms,you can kill the unix/vms shadow process directly. Is is not recommended.
When killing the shadow process, please be careful of shared servers in a multi-threaded environment.
e.g.
kill -9 6246   (shadow process on unix)
stop/id= (PROC SPID=SESS SPID on vms running single task) 

To find process information, one can execute this query:

column "ORACLE USER" format a11
column SERIAL# format 9999999
column "OS USER" format a8

    select distinct substr(s.username,1,11) "ORACLE USER", p.pid "PROCESS ID",
       s.sid "SESSION ID", s.serial#, osuser "OS USER", p.spid "PROC SPID",
       s.process "SESS SPID", s.lockwait "LOCK WAIT"
    from v$process p, v$session s, v$access a
    where a.sid=s.sid and
       p.addr=s.paddr and
       s.username != 'SYS'
       and a.sid in (select l.sid from v$lock l
                      where (id1,id2) in
                            (select b.id1, b.id2 from v$lock b where b.id1=l.id1 and
                             b.id2=l.id2 and b.request>0));

ORACLE USER PROCESS ID SESSION ID  SERIAL# OS USER  PROC SPID SESS SPID LOCK WAI
----------- ---------- ---------- -------- -------- --------- --------- --------
SCOTT               17         11     3313 oracle8i 6247      6246      801113A4
SCOTT               20         19     3611 oracle8i 6258      6257