How to kill Inactive sessions in ORACLE?

step 1. Find total session details.

SQL> select status,count(*) from v$session group by status;

Step 2. Find sid & serial# for inactive sessions.

SQL> SELECT sid, serial#, status, username FROM v$session where status='INACTIVE';

Step 3. Kill the session using the below command.

SQL> ALTER SYSTEM KILL SESSION 'sid,serial#' IMMEDIATE;

If you have multiple sessions for killing, you must prepare the script.

Script for all sessions:

SQL> SELECT 'ALTER SYSTEM KILL SESSION '''||sid||','||serial#||''' IMMEDIATE;' FROM v$session;

The script is only for Inactive sessions:

SQL> SELECT 'ALTER SYSTEM KILL SESSION '''||sid||','||serial#||''' IMMEDIATE;' FROM v$session 
     where status='INACTIVE';

The above queries will write the queries for you to kill Inactive sessions. It makes your task very easy.