Example: I have two tables in my database called classA and classB, and one table called classA_classB. The last one just defi
Depends on whether or not the relationship (lets call it R) is symmetric. If so then person1, person2 is fine since R(person1, person2) = R(person2, person1). If they are not symmetric then the names should probably reflect an "agent and patient" relationship. So use a word to denote the agent and one to denote the patient, e.g. Befriender, Friend.
Parent and Child or Owner and Child is the generally accepted solutions.
related_id or associated_student_id would be my preference.