Need 3 changes in a MySql Script

Need 3 changes in a SQL Script Users will add the IP address to a database using this link The database is a *.db file http://<ipaddr>/autoadd?username=username>&password=password 1. After the IP is written in the database at the same time the IP is written into the /etc/iptables/[login to view URL]' file The current problem is, you can add the same IP multiple times into the database and the same IP is written multiple times in the /etc/iptables/[login to view URL]' file We need to solve: - Check if the IP already exists in the database, if the IP addres is the same "do nothing" - If there is a new IP: delete the old IP from the database and add the new IP into the database - as well we need to delete the old IP in the /etc/iptables/[login to view URL] and add the new IP into /etc/iptables/[login to view URL] 2. If the account from an user is expired in the database we need to delete his IP from the database and delete it from the file and from /etc/iptables/[login to view URL] I prefer a freelancers from Ukraine and Russia Thanks