Database Systems

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Ø  The difference between data and information

·         Data

Data are raw facts. The word raw indicates that the facts have not yet been processed to reveal their meaning

Example: surveying users to assess the computer lab’s performance.
Make a web survey form that enables users to respond to your questions. When the survey form has been completed, the form’s raw data are saved to a data repository. Although you now have the facts in hand, they are not particularly useful in this format
Therefore, you can transform the raw data into a data summary format or graph format. It can quickly extract the meaning of raw data


·         Information

Information is the result of processing raw data to reveal its meaning.

In this “information age,” production of accurate, relevant, and timely information is the key to good decision making.

In turn, good decision making is the key to business survival in a global market.

Ø  What is a database and What is a DBMS ? 

A database is a shared, integrated computer structure that stores a collection of:
·         End-user data - that is, raw facts of interest to the end user.
·         Metadata or data about data - through which the end-user data are integrated and managed.

A database management system (DBMS) is a collection of programs (software) that manages the database structure and controls access to the data stored in the database. The DBMS serves as the intermediary between the user and the database.

A DBMS provides advantages such as:

·         Improved data sharing.
·         Improved data security - provides a framework for better enforcement of data privacy and security policies
·         Better data integration – when data is integrated, it provides a clearer view of the big picture. (see how actions in one segment of the company affect other segments) 
·         Minimized data inconsistency - For example, data inconsistency exists when a company’s sales department stores a sales representative’s name as “Bill Brown” and the company’s personnel department stores that same person’s name as “William G. Brown”
·         Improved data access - The DBMS makes it possible to produce quick answers to ad hoc queries
·         Improved decision making
·         Increased end-user productivity



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