Record-based Logical Models
Next: The Relational Model
Up: Data Models
Previous: The Object-Oriented Model
Record-based logical models:
- Also describe data at the conceptual and view levels.
- Unlike object-oriented models, are used to
- Specify overall logical structure of the database, and
- Provide a higher-level description of the implementation.
- Named so because the database is structured in fixed-format
records of several types.
- Each record type defines a fixed number of fields, or attributes.
- Each field is usually of a fixed length (this simplifies the
- Record-based models do not include a mechanism for direct
representation of code in the database.
- Separate languages associated with the model are used to express
database queries and updates.
- The three most widely-accepted models are the relational,
network, and hierarchical.
- This course will concentrate on the relational model.
- The network and hierarchical models are covered
in appendices in the text.
Page created and maintained by Osmar R. Zaï ane
Sun Sep 10 16:58:49 PDT 1995