Views of Data
September 17, 2016
Categorised in: Database Management System
A major purpose of DBMS is to provide users with an abstract view of the data. There are 3 levels of abstraction.
- Physical Level: Describes how the data are actually stored (complex low-level data structures in detail)
e.g. customer, account, employee record
- Logical View: Describes what data are stored in database and relationships.
e.g. data type of data
- View Level: Describes only part of entire database.
e.g. application programs to display data