The EntityRelationship Model R &G - Chapter 2 A relationship, I think, is like a shark, you know? It has to constantly move forward or it dies. And I think what we got on our hands is a dead shark. Woody Allen (from Annie Hall, 1979) Databases Model the Real World • “Data Model” allows us to translate real world things into structures computers can store • Many models: Relational, E-R, O-O, Network, Hierarchical, etc. • Relational – Rows & Columns