6 phases in the process of developing an information system

6 phases in the process of developing an information system

Nowadays, millions of people are using functions in the information system.

Have you ever wondered: what phase was an information system (Information System) developed? The following article will partially answer those questions.

Phase 1: Project  survey

A current status survey is the first stage in the Information system development system. The main mission of this task is to find out, collect the necessary information to prepare for the project's requirement. Survey stage is divided into 2 steps:

Step 1:

• Preliminary survey: understanding the basic factors (organization, culture, characteristics, people, ...) creating a premise for the development of information systems which are suitable with projects and businesses.
• Detailed survey: collect detailed information about the system ( processing function, information allowed to enter and exit the system, constrain, basic interfaces, business) for analysis and design. 

Step 2: Set out the main issues that need to be solved, such as:

• How to input information in the system? 
• The differences between display and output data.
• How are constraints between objects in the system to be built?
• Which requirements and functions of the system must meet the requirements?
• What solutions should be used? What is the feasibility of each solution?

From the information collected and the issues raised during the survey, administrators and experts will select the necessary elements to constitute a separate information system for businesses.

Phase 2: System analysis

The objective of this stage is to determine the information and processing function, detail as below: 

• Determine the Information System requirement including main - supporter function, the accuracy of the business ensuring, compliance with current laws and regulations, Ensuring processing speed and upgrades in the future.
• Analysis and specification of the overall functional hierarchy model through BFD (Business Flow Diagram) diagram, from BFD model, will continue to be built into DFD data flow model (Data Flow Diagram) through the functional decomposition process at levels 0, 1, 2 in each treatment cell.
• Data table analysis. What data table including data field do you need to put in system? Determine the primary key, foreign key as well as the relationship of data tables and necessary data constraint. 

At this stage, experts will have the preliminary specification of data table on paper to have an objective view. Thereby, determine the best solution for the system to make sure the requirements surveyed before performing on specialized software.

Phase 3: Design 

Through information collected in the survey and analysis survey, experts will convert into software, specialized tool to specify detailed system design. This stage will be divided into 2 steps: 

Step 1: General design

Based on the data analysed and specified on paper, they will be designed as a conceptual model by specialized software such as Sybase PowerDesigner, CA ERwin Data Modeler. By conceptual model, experts will have the most overview of the relationship of objects before changing into the physical model.  

Step 2: Detailed design

• Database design: The code is generated into a SQL file with a full physical level model during the general design phase.
• Query, procedure, function design: collect, process the input information and giving accurate information. 
• Design program interface which is suitable with environment, culture, and requirement of the enterprise.
• The program function design ensures the logic of data entry and processing for users.
• Design report. Based on the requirement of enterprise and current, report template will be designed or allow the enterprise to create a report on the system
• Design of controls by giving specific notices, warnings or errors to facilitate and strictly control the input process with the aim of increasing the accuracy of the data.

In summary, the design is the application of tools, methods and procedures to create the system model. The final product of the design stage is the system specification in the form it exists in such a way that programmers and infrastructure engineers can easily convert it into program and system architecture.

Phase 4: Performance

This stage will develop the system according to determined designs and include the following steps: 

• Select the database management system (SQL Server, Oracle, MySQL, etc.) and install database for system
• Select the programming tool to develop programming module of the system (Microsoft Visual Studio, PHP Designer, etc.).
• Select tools to develop system interface (DevExpress, Dot Net Bar, etc.).

Write instruction, technical document and instruction clip.

Phase 5: Testing

• Firstly, select the testing tool. 
• Verify the functional modules of the information system, convert designs into programs (software).
• Testing information system.
• Finally, fix bugs (if any)
• Write test case as required.

The final result is an information system that meets the requirement.

Phase 6: Deployment and maintenance

• Hardware installation as a base for the system.
• Software setting 
• Convert activities of the old system into the new one, including data conversion, personnel arrangement and management working in the system, management system and maintenance organization.
• Find out bugs, errors of Information system
• Training and instruction.
• Information system improvement and edition.
• Guarantee
• Upgrade when having new version.