Database Management System
4.1 Introduction to Database
A database is a collection of organized data that can be easily accessed, managed, and updated.
4.2 Types of Databases
- Flat-File Database: A simple database that stores data in a single table.
- Relational Database: A database that stores data in multiple tables with relationships between them.
- Object-Oriented Database: A database that stores data in the form of objects.
- NoSQL Database: A database that does not use the traditional table-based relational model.
4.3 Database Management System (DBMS)
A DBMS is a software system that allows you to define, create, maintain, and manipulate databases.
4.4 Characteristics of DBMS
- Data Independence: The ability to change the database structure without affecting the applications that use it.
- Data Integrity: The ability to ensure that the data in the database is accurate and consistent.
- Data Security: The ability to control access to the database and prevent unauthorized changes.
- Data Recovery: The ability to recover the database in case of a failure.
4.5 DBMS Components
- Database Engine: The component that manages the database and performs operations such as creating, modifying, and querying the database.
- Database Schema: The component that defines the structure of the database, including the tables, fields, and relationships.
- Database Query Language: The component that allows users to interact with the database and perform operations such as querying and modifying the data.
4.6 Popular DBMS
- MySQL: A popular open-source relational database management system.
- Microsoft SQL Server: A commercial relational database management system developed by Microsoft.
- Oracle: A commercial relational database management system developed by Oracle Corporation.
- MongoDB: A popular open-source NoSQL database management system.
4.7 Database Design
- Entity-Relationship Diagram (ERD): A diagram that represents the entities and relationships in a database.
- Normalization: The process of organizing the data in a database to minimize data redundancy and improve data integrity.
4.8 Summary
In this chapter, we learned about the basics of database management systems, including types of databases, DBMS characteristics, components, and popular DBMS. We also learned about database design, including ERDs and normalization.
4.9 Exercises
1. What is the difference between a flat-file database and a relational database?
2. What are the characteristics of a DBMS?
3. What are the components of a DBMS?
4. What is the purpose of database design?
5. What is normalization in database design?
4.10 Key Terms
- Database
- Database Management System (DBMS)
- Relational Database
- Object-Oriented Database
- NoSQL Database
- Data Independence
- Data Integrity
- Data Security
- Data Recovery
- Entity-Relationship Diagram (ERD)
- Normalization
