Get value from one table and insert it into another table based on a range of data

I have two tables: database & authorityMatrix .

When a new record hits database, it has a field called: cost

In the authorityMatrix, I have a table with names, emails, and approvalAmounts. The approvalAmounts are the highest Costs that person can approve.

Basically I want to do a lookup on the authorityMatrix, and assign the appropriate approvingAuthority into the database based on the level they can approve.

I imagine the evaluation would be something like: where authorityMatrix.approvalAmounts <= database.cost and lowestApprovalAuthority = ‘Yes’

This should insure that the lowest level person has already OK’d it to go up to the next level. If they are the FINAL approval, then I’d want to trigger a field that says Final … but that’s getting more advanced … haven’t though through that logic yet.

Any help getting started would be greatly appreciated.