ERM concepts

Entity relationship diagram

To understand the following mapping rules, you must be familiar with the concepts of the entity relationship model (ERM). Using this flash example, you can refresh your memory about ERM.

hould any of the concepts be new, please consult the following book:

• Fundamentals of Database Systems, Elmasri, Ramez; Navathe, Shamakant B. (1994)

You should be familiar with the following terms: strong entity, weak entity, relationship, identifying relationship, attribute, derived attribute, multivalued attribute, composite attribute, identifier or primary key and discriminator.