database - In a inheritance joined with jpa the tables need pk? And its better have a extra table for role or just have a column role -


i have 3 tables 4 tables, role, person, executive, partner, admin.

person: id, name, phone, address

executive: id_executive, office_number, office_phone, office_email

admin: id_admin

partner: id_partner, phone , email

role: id_role, role_description

i have 2 doubts:

if in inheritance(joined) in jpa need have in tables primary key, example primary key in person table necessary, primary key id_executive on executive table, id_admin primary key in admin table , id_partner in partner table needed? in classes need id in person class, in tables need primary key each table?

if in case 3 tables(admin,partner,executive) better have 4th table role, in 1-to-many relationship person, or if better have column "role" in person table. know option better , why? or icual?


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