Phases In Database Development Process
Phases In Database Development Process: The database development process comprises a series of phases where each of them has its own expertise. The major phases are planning, requirement analysis, and implementation. Each process is divided into steps.
The diagram of these phases are shown as
The planning phase begins when a customer requests to develop a database project. It is a set of tasks or activities, which decide to the resource required in the database development and the time limit of different activities. During the planning phase, four major activities are performed these are
- Review and approve the database project request.
- Prioritize the database project.
- Allocate resources such as money, people, tools, etc.
- Arrange a development team to develop the database project.
Requirement analysis is done in order to understand a problem, which is not solved. It is very important activity for the development of database system in the development life cycle of the database. The person responsible for requirement analysis id called Analyst. In requirement analysis phase the requirement and the expectation of the users are collected and analyzed. The collected requirements help to understand the system what does not yet exist in the required form.
There are two major activities in requirement analysis. These are
- Problem Understanding or analysis.
- Requirement specification.
Steps in Analysis
There are the following steps included in requirement analysis.
- Develop Conceptual Data Model
- Develop Process Model
- Data Flow Diagram
The design is the major phase of database development process. In this phase, the information model that we developed during analysis are used to design a conceptual schema for the database and to design application. It is an important phase of the phases in database development process.
In conceptual schema design the data requirements collected in requirement analysis phase are examined and a conceptual database schema is produced which is more important in the design phase of the database development process. In transection and application design the database application analyzed in requirement analysis phase are examined and the specification of these application are produced.
The major two steps in design phase are
- Database Design
- Process Design
In this phase the appropriate DBMS is selected to support the information system. A number of factor are involved in DBMS selection. They may be technical and economical factors.
The technical factors are concerned with the suitability of the DBMS for information system. The following technical factor are considered
- Type of DBMS such as relational, object-oriented etc.
- Storage structure and access methods that the DBMS supports with in the database .
- Interfaces available for users and programmers.
- Types of query language.
- Development tools.
The financial factor are concerned with the cost of DBMS and to operate it. In this case the following costs are considered
- Software Cost
- Maintenance Cost
- Hardware Cost
- Database Creation and Maintenance Cost
- Training Cost
After the design phase and selecting a suitable DBMS, the database system is implemented or installed for use. The purpose of this phase is to install the information system according to the plan and design as described in previous phase.
Implementation involves a series of steps leading to operational information system that includes creating database definitions, development applications, testing the system, developing operational procedure and documentation, training the users and populating the databases in the same data file of the same organization. It is an important phase of phases in database development process.
Implementation involves two steps, these are
- Database Definition
- Creating application
Once the database is implemented the maintenance phase of the database system begins. The maintenance is the process of monitoring and maintaining the database system. Maintenance includes activities such as adding new fields, changing the size of existing file, adding new tables and so on.
As the database system requirement change, it become necessary to add new table or remove existing tables and to recognize some files by changing primary access methods or by dropping old indexes and constructing new ones. Some quires may be rewritten for better performance. Database tuning or reorganization continues throughout the life of database, while the requirement keep changing.