IN a large organisation, the database system is typically part of the information system which includes all the resources that are involved in the collection, management, use and dissemination of the information resources of the organisation. In the today’s world these resource includes the data itself, DBMS software, the computer system software and storage media, the person who uses and manages the data and the application programmers who develop these application. Thus the database system is a part of much larger organizational information system.
In this article we will discuss about typical life cycle of an information system, and how the database fits into this life cycle. Information cycle is also known as Macro life cycle.
These cycle typically includes following phases:
- Feasibility Analysis –
This phase basically concerned with following points:
- (a) Analyzing potential application areas.
- (b) Identifying the economics of information gathering.
- (c) Performing preliminary cost benefit studies.
- (d) Determining the complexity of data and processes.
- (e) Setting up priorities among application.
- Requirements Collection and Analysis –
In this phase we basically do the following points:
- (a) Detailed requirements are collected by interacting with potential users and groups to identify their particular problems and needs.
- (b) Inter application dependencies are identified.
- (c) Communication and reporting procedures are identified.
This phase has following two aspects:
- (a) Design of database
- (b) Design of application system that uses and process the database.
- Implementation –
In this phase following steps are implemented:
- (a) The information system is implemented
- (b) The database is loaded.
- (c) The database transaction are implemented and tested.
- Validation and Acceptance Testing –
The acceptability of the system is meeting’s users requirements and performance criteria is validated. The system is tested against performance criteria and behavior specification.
- Deployment operation and maintenance –
This may be preceded by conversion of users from older system as well as by user training. The operational phase starts when all system function are operational and have been validated.As new requirements or application crop up, they pass through all the previous phases until they are validated and incorporated into system. Monitoring and system maintenance are important activities during operational phase.