Page 1 - Relational Databases

Database Management Systems

Data - Collection of raw facts and figures

Information - Processed data is called information

Database is a collection of related data and data is a collection of facts and figures that can
be processed to produce information.

A database management system (DBMS) is a software application that allows a user to
define, create, and maintain a database while providing a way to maintain multiple access
control and security of the data.

Examples of DBMS are: Ms-Access, MySQL, PostgreSQL, SQLite, Microsoft SQL Server,
Oracle, SAP, dBASE, FoxPro, etc.

A DBMS gives us tool to:
 Store data in a structured way
 Query the database
 Sort and manipulate the data in the database.
 Validate the data entered and check for inconsistencies
 Produce flexible reports, both on screen and on paper, that make it easy to
comprehend the information stored in the database.
 Maintains inconsistency in case of multiple users.

Components of a DBMS

1. Users - users are of various types: administrator,
System or Application developers and end user.
2. Database Application – Database application may be
Personal, Departmental or Enterprise. It may be
general purpose or customized as per the needs of
the user.
3. DBMS – It is the software that allows users to define,
create, access and manage database(s). Ex. MySQL,
Oracle etc.
4. Database – It is a collection of logical data.

Users of DBMS

A typical DBMS has users with different rights and permissions who use it for different
purposes. Some users retrieve data and some back it up. The users of a DBMS can be
broadly categorized as follows −
Administrators − Administrators maintain the DBMS and are responsible for administrating
the database. They are responsible to look after its usage and by whom it should be used.