(197)-DATABASES

Databases

A database may be described as a “pool” of data, which can be used by any number of applications. Its use is not restricting to the accounts department. A stricter definition is provided in the computer terminology of the CIMA.

“Frequently a much abused term, in its strict sense a database is a file of data structured in such a way that it may serve a number of applications without its structure being dictated by anyone of those applications. The idea is that programs are written around the database rather than files being structured to meet the needs of specific programs. The term is also rather loosely applied to simple file management software”.

The software that runs the database is called the database management system (DBMS). The CIMA’s definition is as follows.

“Technically a database management system is a system which uses a database philosophy for the storage of information in practice this term is often used to describe any system which enables the definition, storage and retrieval of information from discrete files written a system. Thus, many simple file can be handling systems are frequently referred to as database system.












Note the following from the diagram.

• Data is input, and the DBMS software organizers it into the database if you like you can think of the database as a vast library of files and records, waiting to be used.
• Various application programs are “plugged into” the DBMS software so that they can use the database, or the same application used by different departments can all use the database.
• As there is only one pool of data, there is no need for different departments to keep many different files with duplicated information.

Objective of a data base

The main virtues of a database are as follow.

• There is common data for all users to share.
• The extra effort of keeping duplicate files in different department is avoided.
• Conflicts between departments who use inconsistent data are avoided.

A database should have four major objectives.

1. It should be shared.
2. The integrity of the database must be preserved.
3. The database system should provide for the needs of different users.
4. The database should be capable of evolving, both in the short term and in the longer term.