Record based logical models, Database Management System

Record based Logical Models: Use records as the key data representation components

Examples:

Relational Model: It shows data as well as relationship between data in the form of tables.

Constraints are stored in a meta-data table. This is a very easy model and is based on a proven mathematical theory. This is the most usually used data base model.

Network Model: In this model data is shown as records and relationship as links. A easy network model example is explained in Figure . It shows a sample diagram for such a system. This model is a very good quality model as far as conceptual framework is concerned but is today not used in database management systems.

Posted Date: 3/6/2013 5:08:32 AM | Location : United States







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