DATABASE MANAGEMENT SYSTEM &

ITS COMPONENTS

A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports processes requiring this information (for example, finding a hotel with vacancies). The term "database" refers both to the way its users view it, and to the logical and physical materialization of its data, content, in files, computer memory, and computer data storage.

Banking : For customer information , accounts and loans, and banking transaction

Airlines : For reservations and schedule information . Airlines were among the first to use database in a geographically distributed manner – terminals situated around the world accessed the central database system through phone lines and other data network

Universities : For student information , course registration and grades

Telecommunication : For keeping records of calls made , generating monthly bills etc .

Sales : For customer , product , and purchase information

A database management system (DBMS) is a software package with computer programs that control the creation, maintenance, and the use of a database. It allows organizations to conveniently develop databases for various applications by database administrators (DBAs) and other specialists.

Together the database and DBMS software is called as Database system . Users of the system can perform a variety of operations –for example :

Adding new , empty files to the database Inserting data in to existing file Retrieving data from the existing file Changing or modifying data in existing

file

Deleting data from existing file

Removing existing file

And most importantly extracting data from existing file

Data independence Efficient data access Data integrity & security Data administration Concurrent access, crash recovery Reduced application development time So why not use them always ?

Expensive/complicated to set up & maintain This cost & complexity must be offset by need General-purpose, not suited for special-purpose

tasks (e.g. text search!)