DBMS
Why DBMS?
• Application must stage large datasets between main memory and
secondary storage
(e.g., buffering, page-oriented access, 32-bit
addressing, etc.)
 Special code for different queries
 Must protect data from inconsistency due to
multiple concurrent users
 Crash recovery
 Security and access control
Database Management System
 Collection of programs that enables users to create and maintain
a database.
 Software system that facilitates the processes of defining,
constructing and manipulating databases for various applications.
 Defining-specifying the data types, structures and constraints for
the data to be stored.
 Construction -storing the data itself on some storage medium
that is controlled by the DBMS.
 Manipulation -querying, retrieving, updating and report
generating.
Advantages of using a DBMS
1. Controlling redundancy-avoids duplication of
data, waste of space and inconsistency of data.
2. Restricting unauthorized access
3. Providing persistent storage for program objects
and data structures.
4. Providing multiple user interfaces
5. Representing complex relationships among data
6. Enforcing integrity constraints
7. Provide backups and recovery