To get a list of running SQL queries, log into the PostgreSQL CLI:

psql -U username database

Replace username and database with the proper values. Then run this query:

SELECT procpid,datname,usename,client_addr,waiting,query_start,current_query FROM pg_stat_activity;

Inside the list is also the procpid, which you will need to kill a running query. To kill, run this query, substituting with the proper procpid:

SELECT pg_cancel_backend(procpid);

To have scripted automated backup of PostgreSQL databases on a linux platform, you can create a script like so:

#!/bin/bash
PGPASSWORD="your-password" /usr/bin/pg_dump -U user database > sql-file.sql

Replace user and your-password with your username and password; replace database with the database you want to backup. The output of the dump goes to stdout and can be piped to a plain text file or compressed to something else.