Default custom DFF value based on information from all PR Lines

Summary:

Is it possible to write custom SQL for a custom DFF that would default a value based on information on all the PR Lines and not on the specific Line?

Content (please ensure you mask any confidential information):

Scenario:

• Add a custom DFF at PR Line level that would default to a value based on the Purchasing Category - currently supported. For example, in a PR, we have two Lines for two different Purchasing Categories and therefore DFF Line 1 would default to CM1 and DFF Line 2 to CM2 based on a mapping set. This, in our case, would list the group of Category Managers required to approve that particular Category.