Software Engineering | Database application system life cycle

Database application development is basically the process of obtaining following things.

1. Real-world requirements
2. Analyzing the real-world requirements
3. To design the data and functions of the system
4. Implementing the operations in the system.

Activities related to the database application system (micro) life cycle include the following:

1. System Definition –
The scope of the database system, its users, and its application are defined.The interfaces for various categories of users, the response time constraints and storage and processing needs are identified.

2. Database design –
At the end of this phase a complete logical and physical design of the database system on the chosen DBMS is ready.

3. Database implementation –
This comprises the process of specifying the conceptual, external, and internal database definition creating empty database files, and implementing the software application.

4. Loading or data conversion –
The database is populated either by loading the data directly or by converting existing files into database system format.

5. Application conversion –
Any software application from a previous system are converted to the new system.

6. Testing and Validation –
The new system is tested and validated. Testing and validation of application programs can be a very involved process and the techniques that are employed are usually covered in the software engineering course. The automated tools that assist in the process.

7. Operation –
The Database system and its application are put into operation Usually the old and new system are operated in parallel for some time.

8. Monitoring and Maintenance –
System is constantly monitored and maintained during the operational phase. Growth and expansion can occur in both data content and software application.
Database basically needs to be modified and recognized from time to time.

Activities 2, 3, 4 are part of the design and implementation phase of the larger information system life cycle. Most databases in organization undergo all the preceding lifecycle activities. Most databases undergo all the preceding life cycle activities. The conversion activities(4 and 5) are not applicable when both the database and application activities are new.When an organization moves from an established system to a new one activities 4 and 5 tend to be the most consuming and the effort to accomplish them is often underestimated. In general there is often feedback among the various steps because new requirements frequently arises at every stage.