I'm Using porgressql and i need to help the query to update Technichian to associate site and group.

ex:

We have 100 Site and 50 Technichian,5 support group, our workflow is only the people in a group with a specified site can populate in request template, and the prolem is my company change the technichian with the site everyweek, and we can't take 1 or 2 hour every week to update it,so any tool ,api or something to help up update it ?

Thanks.