build a page to execute a query

Hi I have struggled over the last year or so to build a php database for a sporting association, it is working well. Have been trying to build a scoring system and have it working, but it is cumbersome to use.... Have written this query and tested from the cpanel in phpmyadmin UPDATE `mydatabase`.`xxscrs` SET `RP_bill`=(SELECT SUM(xxscrs.player_total)*50) Obviously it updates the whole table and calculates a players "ranking points" that is what I want it to do. What I would like is to have a page in the database so when scores have been inserted/updated in the "xxscrs" table, it can then be updated by running the query. I do not have the skill to write this page so if anyone is interested?