which one is foreign key and primary foreign key in above solution

In the provided solution:

Appointment (vetID PK, vetName, PetID PK, PetName, PetType, OwnerMobile, OwnerFullName, channelID PK, channelName, date, time)

The primary keys (PK) are vetID, PetID, and channelID. These are the unique identifiers for each vet, pet, and channel respectively.

There are no foreign keys (FK) in this relation as it stands. A foreign key would be a field in this table that is a primary key in another table. For example, if there were separate tables for Vet, Pet, and Channel, then vetID, PetID, and channelID could be foreign keys in the Appointment table, referring to records in those other tables.

A primary foreign key (PFK) is a field that serves as both a primary key and a foreign key. In this relation, there are no fields that serve as both a primary key and a foreign key, so there are no primary foreign keys.

Please note that in a real-world scenario, we would likely have separate relations for Vet, Pet, Owner, and Channel, and the Appointment relation would include foreign keys to these relations. However, based on the given information and constraints, this is the relation.