Data Models
Data Models Consider a simple student registration. Specifically we want to support the tasks of students registering for or withdrawing from a class. To do this, the system will need to record data about what entities? What specific data about the entities will need to be stored? What is the cardinality between students and courses? Diagram the data model. While, considering a student class registration system for registering or withdrawing a system must have the capability to record data in regards to certain entitites. Specifically, student data, system data, service data, service type, class type, and class information all must be stored on the system. Student data such as age, contact information, student major data all must be recorded. System data such as tuition payment method, and registration method must also be recorded. Service data such as the data classes begin, and the number of classes must also be recorded. Service type such as tutoring, computer lab information, extra curricular pricing, and materials for the class must also be recorded. Class state, such as size of the class, and whether the class is properly manned is also important information that must be recorded. Finally, class data such as the type of class, the instructor of the course, and concentration information is also important. A connector has cardinality, which means how many connections X has to Y, or Y has to X. In this example, the student has multiple connections to the class, and the class has multiple connections to the student.
Example of a data model for a Class registration System:
Figure 1-1
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The local library wants to update its book check process. To do this, the system will need to record data about what entities? What specific data about the entities will need to be stored? Diagram the data model.
A data model, “specifies the data that is to be stored in the system and the relationships between the data”
References: Soren Lausesen. (2002). Software Requirements, Styles and Techniques. Great Britain: Addison-Wesley