Monday, October 1, 2012

Part 4.5 Physical Data Modeling


Physical Database Design

Physical database design is the process of developing a set of required data structures on a selected database. It involves the following tasks:
  • Converting entities into tables
  • Converting relationships into foreign keys
  • Converting attributes into columns
  • Defining constraints
 The purpose of physical design is to optimize performance as closely as possible.







 Along with the logical data model, the database designer requires the following to make sound design decisions:

  • The Process Model, detailing input processes (creation and updating of rows in tables) and output requirements (retrieval of data from the database)
  • The mapping that shows the processes that access each entity class and how (create, update, retrieve)
  • Nonstructural data requirements
  • Performance requirements
  • The target DBMS
  • Disk space requirement
  • Availability of skilled programming resources