State 1: Project survey
A status survey is the first stage in the development of an information system. The main task in this phase is to learn and collect the necessary information to prepare for the resolution of the project’s requirements. The survey phase is divided into two steps:
- Preliminary survey: learn the basic factors (organization, culture, characteristics, people, …) creating a premise to develop an information system suitable to the project and the business.
- Detailed survey: collect detailed information of the system (processing functions, information allowed to enter and exit the system, constraints, basic interface, business) for analysis and design
Step 2: Set key issues that need to be solved, such as:
– How should information be entered into the system?
– What is the difference between display and output data?
– How are the constraints between the objects in the system to be built?
– What are the requirements of the system’s functions and processes?
– What solutions should be used? What is the feasibility of each solution?
From the information collected and the problems posed in the survey phase, administrators and experts will select the necessary elements to form a separate information system for the business.
Stage 2: System analysis
The goal of the phase is to define the information and processing functions of the system, specifically as follows:
Determine the requirements of the Information System, including: main – secondary functions; The business needs to be handled to ensure accuracy, in compliance with current legal documents and regulations; ensure processing speed and future upgradeability.
Analyzing and specifying the overall functional hierarchy model through the BFD (Business Flow Diagram) diagram, from the BFD model will continue to be built into the DFD (Data Flow Diagram) data flow model through the process. functional decomposition according to levels 0, 1, 2 in each processing cell.
Data table analysis. What data fields should be included in the system? Determine the primary key, foreign key as well as the relationship between the data tables (relationship) and the required data constraint.
At this stage, experts will preliminarily specify the data sheets on paper to have an objective view. Thereby, determining the best solutions for the system to ensure the correct requirements are surveyed before implementing on specialized software.
Stage 3: Design
Through the information collected from the survey and analysis process, experts will transform it into specialized software and tools to specify the detailed system design. This phase is divided into two steps:
Step 1: Overall design
On the basis of the analyzed data tables and specifications on paper, it will be designed as a conceptual model by specialized software such as Sybase PowerDesigner, CA ERwin Data Modeler. By conceptual level model will give experts the most general view of the relationship between objects before converting to physical level model.
Step 2: Detailed design
- Database design (Database): With a complete physical-level model at the general design stage, the code will be generated into a sql file.
- Design queries, procedures, functions: collect, process input information and provide accurate information according to the right business.
- The program interface design is suitable for the environment, culture and requirements of the enterprise implementing the project.
- Design program functions to ensure logic in the process of data input and processing for users.
- Report design. Based on the requirements of each enterprise and current regulations, appropriate report templates will be designed or allowed for private enterprises to create report templates right on the system.
- Design controls in the form of specific messages, warnings or errors to facilitate and strictly control the data entry process with the goal of increasing data accuracy.
- In short, design is the application of tools, methods, and procedures to create a model of the system to be used. The final product of the design phase is the specification of the system in its actual form, so that programmers and hardware engineers can easily translate the program and structure of the system.
Stage 4: Implementation
This is the stage to build the system according to the defined designs. This phase includes the following tasks:
- Select the database management system (SQL Server, Oracle, MySQL, …) and install the database for the system.
- Select programming tools to build system program modules (Microsoft Visual Studio, PHP Designer,…).
- Select tools to build system interfaces (DevExpress, Dot Net Bar,…).
- Write user manuals, technical documents or instructional clips.
Stage 5: Testing
- First of all, you have to choose a test tool.
- Verify functional modules of information systems, convert designs into programs (software).
- Information system testing.
- Finally, fix the errors (if any).
- Write test cases as required.
- The end result is a satisfactory information system.
Stage 6: Deployment and maintenance
- Install the hardware to base the system on.
- Install software.
- Converting the operation of the old system to the new system, including: data conversion; arrange and arrange people to work in the system; organization management and maintenance system.
- Detect errors and shortcomings of information systems.
- Training and manuals.
- Improve and edit information system.
- Upgrade the program when a new version is available.