Database Management System (DBMS)

 

Introduction

• A database is the collection of related persistent data and contains information relevant to an enterprise. The database is also called the repository or container for a collection of data files. 
• For example, university database for maintaining information about students, courses and grades in university.
• A database system is basically just a computerized record-keeping system. A database system involves four major components: data, hardware, software, and users.
• The database management system (DBMS) is the software that handles all access to the database. It is defined as the collection of interrelated data and a set of programs to access those data.

Users of a DBMS system can perform the following basic operations on the database:

• Adding new, empty files to the database. 
• Inserting data into existing files.
• Retrieving data from existing files. 
• Changing data in existing files. 
• Deleting data from existing files. 
• Removing existing files from the database.  

An example:

UNIVERSITY database 

 ❖ Information concerning students, courses, and grades in a university environment.

Data records 

❖ STUDENT 

❖ COURSE 

❖ SECTION 

 ❖ GRADE_REPORT 

 ❖ PREREQUISITE  

Database Application 

➢ Databases form an essential part of almost all enterprises. Some database applications are given below: 

❖ Banking: For customer information, accounts, and loans, and banking transactions. 

❖ Airlines: For reservation and schedule information. 

❖ Universities: For student information, course registrations, and grades. 

❖ Credit card transactions: For purchase on credit cards and generation of monthly statements. 

❖ Telecommunication: For keeping records of call made, generating monthly bills, maintaining balances on prepaid calling cards, and storing information about the communication networks. 

❖ Finance: For storing information about holdings, sales, and purchase of financial instruments such as stocks and bonds

❖ Sales: For customer, product, and purchase information. 

❖ Manufacturing: For management of supply chain and for tracking production of items in factories, inventories of items in warehouses/stores, and orders for items. 

❖ Human resources: For information about employees, salaries, payroll taxes and benefits, and for generation of paychecks.