Object-based Logical Models

1. Object-based logical models:
   • Describe data at the conceptual and view levels.
   • Provide fairly flexible structuring capabilities.

   • Allow one to specify data constraints explicitly.

   • Over 30 such models, including
     • Entity-relationship model.
     • Object-oriented model.
     • Binary model.

     • Semantic data model.
     • Infological model.
     • Functional data model.
2. At this point, we'll take a closer look at the entity-relationship (E-R) and object-oriented models.

• The E-R Model
• The Object-Oriented Model