title: How do we implement an IS-A Relationship?
body: <p>We implement an One-to-Many relationship by adding one Table's PK, as FK to the other Table.
  We implement a Many-to-Many relationship by adding 2 Table's PKs to a third Table.</p>
  
  <p>How do we implement an IS-A Relationship ?</p>
  
  <p>The Entities are TECHNICIAN and ADMINISTRATIVE which both are EMPLOYEE.
  I could just use an extra field in the Table 
  EMPLOYEE(id, name, surname, <strong>role</strong>, ...AdminFields..., ...TechFields...)</p>
  
  <p>but i would like to explore the IS-A option.  </p>
  
  <p>EDIT: I did as Donnie suggested, but without the role field.</p>