Find and kill the hang query or session in PostgreSQL

Check all the running processes in PostgreSQL

SELECT pid,user,query FROM pg_stat_activity WHERE state = 'active';

Terminate the execution of the query which you want to stop:

Get the process id from the first command and cancel the query with the use of the following command :

SELECT pg_cancel_backend(PID);

Terminate the complete session :

To kill or terminate the session of the user running or executing a hanging query:

SELECT pg_terminate_backend(PID);