The requirements analysis phase answers the question, "What does the user need and want from a new system?" The requirements analysis phase is critical to the success of any new information system! In this milestone we need to identify what information systems requirements need to be defined from the system users' perspectives and draw graphical, logical models to document the data requirements for a new and improved system.
Data modeling is a technique for organizing and documenting a system's data. Data modeling is sometimes called database modeling because a data model is usually implemented as a database. Data is viewed as a resource to be shared by as many processes as possible. As a result, data must be organized in a way that is flexible and adaptable to unanticipated business requirements - and that is the purpose of data modeling.
In this milestone, you will first discover those entities in the system that are or might be described by data. Then you will define each entity you identify in respect to the business in an Entity Definition Matrix. Then you will do the data model tutorial in doc sharing that will prepare you for doing the logical entity relational diagram (ERD).
Objectives
After completing this milestone, you should be able to:
• Understand and perform the techniques for entity discovery.
• Define each entity with respect to the business and complete an entity definition
matrix.
• Perform the necessary data modeling techniques to organize and document the
data requirements for the proposed system.
• Construct the Context data model (Logical ERD).
Prerequisites
Before starting this milestone, the following topics should be covered:
• Data modeling - Chapters 8 and 14.
• Milestone 1-3 Solutions (provided by your instructor)
Assignment
Now that we have studied the current system and analyzed some of its problems and opportunities, plus gained approval to proceed, we can now start to identify the business data requirements and graphically model them. In this assignment, we will use our results of the previous milestones, samples of forms we have collected, and a copy of a transcript of an interview with Dan Stantz's staff. The results of this activity will identify the business data requirements for the proposed system.
Activities
1. Complete an Entity Definition Matrix. Analyze each of the forms referenced by the user interview and make assumptions where necessary. (Note: While it is appropriate to make assumptions, you should document those assumptions and include them in your submission to your instructor.) If you create the matrix in Excel, paste it into a Word document prior to submission.
2. Complete the Visio tutorial which walks you through how to create an Entity
Relationship Diagram (ERD), located in Doc Sharing.
When you have completed the tutorial, paste the diagram you have created to the end
of the Word document that already holds your Entity Definition Matrix.
3. Prepare a Context Data Model.
Deliverable format and software to be used are according to your instructor's specifications. Deliverables should be neatly packaged in a binder, separated with a tab divider labeled "Milestone 4-Part I".