Definition of Database Management System (DBMS) - SS3 ICT Lesson Note
A Database Management System (DBMS) is software that helps users and applications interact with a database by providing a set of functions to define, create, maintain, and query the database. It serves as an intermediary between the user, the application, and the actual data stored in the database.
A DBMS has several key components and functionalities:
- Data Storage: It manages the physical storage of data on disk or in memory, organizing it efficiently to ensure quick retrieval.
- Data Definition Language (DDL): DBMS provides commands to define the structure of the database, including creating tables, specifying data types, and setting constraints like primary keys and foreign keys.
- Data Manipulation Language (DML): It allows users and applications to interact with the data, including inserting, updating, and deleting records, as well as querying the data using languages like SQL (Structured Query Language).
- Data Security: DBMS ensures data security by implementing access control mechanisms, such as user authentication and authorization, to restrict access to sensitive data.
- Data Integrity: It enforces data integrity constraints, like ensuring unique values in a column or enforcing referential integrity between related tables.
- Concurrency Control: DBMS manages multiple users accessing the database simultaneously, preventing conflicts and ensuring data consistency.
- Backup and Recovery: It provides mechanisms to back up the database regularly and recover it in case of data loss or system failures.