Why Database

 

Conventionally, in an information system, the information is obtained by developing the systems and integrating them. This calls for breaking the system into various subsystems and developing the information systems independently.  In this approach, each system will have its master files and transaction files.  They have to be processed separately at different times, depending upon the needs and schedules.  The file layouts and the access methods could be different in different systems. Therefore, the files will be updated at different times. This approach does affect the quality of the information across all the systems due to various reasons.

 

The data in many systems are common, and there is repetition of data storage in various systems. This called data redundancy. The redundancy of data gives rise to problems of keeping the data current and same in all the files.  The data management is complex in such a situation.  The reports generated out of such files show discrepancies in the information.  Since the data files are different for different systems, data sharing is not possible. These files need to be created at different times. Transaction updating is also carried out at different times.  It requires the increase of a magnetic media for storage because the systems are developed independently. The redundancy causes lack of integrity and inconsistency of the data in the various files.