What table structure to use (hibernate)

Question

I hava two entities: PhisicalPerson (PP), JuredicalPerson (JP). And I want to create Phone object. JP has many phones and PP has many phones (one to many relation). So in Phone object I have to create 2 columns for this relations:

class Phone {

 @JoinColumn(name="ppId",nullable=true)
 @ManyToOne
 public PhisicalPerson getPhisicalPerson() {...}

 @JoinColumn(name="jpId",nullable=true)
 @ManyToOne
 public JuredicalPerson getJuredicalPerson() {...}

 // number, city code, additional number and other fields

}

Is it right implementation? Or may be it's better to create different entities: PhisicalPersonPhone and JuredicalPersonPhone?

Answer 1

That's indeed what you could do, but it looks like you have an inheritance relationship here.

Both PP and JP should probably extend a common base entity Person, and it's the Person entity which should have a list of phones. The Phone entity would then just have one ManyToOne association with Person.

That's assuming that the Phone entity needs to know about its owning person. Maybe a unidirectional association would make more sense here. In this case, using a join table (or two, if you don't want this inheritance relationship), would make more sense.