Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

just starting to learn to design. I don't know the term in english to describe this type of design, so I'm here for some help.

Can this "specialitzations" have a relation like this one? Thanks!

enter image description here

share|improve this question
Where is this "specializations"? I can't see it. – ypercubeᵀᴹ Mar 26 '14 at 19:18
Sorry, I don't know how it is in english. Products is divided into natural and artificial. – user47579 Mar 26 '14 at 19:19
Ah ok then. And the question is about the "created by" relationship? – ypercubeᵀᴹ Mar 26 '14 at 19:20
Exactly, sorry! – user47579 Mar 26 '14 at 19:26
Yes, every relation can be related to any other one (or even to itself.) I can't get my head to figure how an ArtificialProduct would be "created by" a NaturalProduct or vice versa but yes, it is allowed. – ypercubeᵀᴹ Mar 26 '14 at 19:28
up vote 1 down vote accepted

Yes, it is allowed. Every relation can be related to any other one (or even to itself.)

The naming does not help much but if the created by means the (natural) "ingredients" that an artificial product is composed of, then it makes sense to use a many-to-many relationship.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.