An Introduction to DBMS
Data Abstraction, Data Modeling, Database Languages in Database Management Systems (DBMS).
Table of Contents
1. Data Abstraction
Data abstraction consists of 3 levels:
- Physical level
- Describes how the data are actually stored in computer system. Focus on low-level data structures and storage details.
- Logical level
- Describe what data are stored, and specifies the relationship among data. And is independent of physical storage.
- View level