Book Image

ASP.NET 3.5 Application Architecture and Design

By : Vivek Thakur
Book Image

ASP.NET 3.5 Application Architecture and Design

By: Vivek Thakur

Overview of this book

Table of Contents (14 chapters)
About the Author
About the Reviewers

Physical Data Model

Once we have defined the logical data model, we can then create a physical data model for our application. A logical model is closer to the business model whereas a physical model actually mirrors the actual database. In short, the physical data model is the logical data model with:

  • Table names for all of logical entities. These table names would be the same as the actual table names in the database.

  • Physical data types and sizes for all of the attributes. In the physical model, we will supply the data types of the entity attributes, such as varchar, int, float, and so on, along with the data type size. Because each database has its own unique set of physical data types, the physical model is dependent upon the type of database being used.

  • Mapping tables or cross tables are used for storing many-to-many relationships within entities. A logical data model might not include mapping tables, but might simply depict such many-to-many relationship between entity A and B using...