Feasibility of Introducing DFFs with Validation for Trade License Details

Dear Oracle Experts,

The customer intends to introduce two new Descriptive Flexfields (DFFs) to capture the Trade License Number and its Expiry Date.

Additionally, they require the application to enforce a validation rule: when creating a new customer, the system should restrict or display an error if the entered Trade License Number already exists for another customer.

Could you please confirm if this functionality is feasible within the current application framework? If so, kindly advise on the recommended approach or configuration steps.

Regards,
Pavan Kumar