Cis: 111 Strayer University Assignment 1 Essay

696 Words Feb 16th, 2015 3 Pages
Assignment 1: Business rules and Data Models
CIS 111: Introduction to Relational Database Management Systems

Purpose of Database
Spellman University had requested that I develop a database for their college. The purpose of the database will be to track the students and the courses. There also will be a place in the system to track the instructors teaching each course. There are many things to be considered in composing this database. This paper will outline the entities, attributes for each entity, the type of relationship, constraints, some business rules, and the conceptual and physical models.
Entities and Attributes of Database There will be three main entities in the system; the students, the instructors and the courses. The
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The students would have to either prolong their time for the course or the institution would have to find more students to fill the second class.
There will be many different constraints in the database. An example of a constraint is one if the students' GPA will have to be between 0.00 and 4.00. Another example would be that each class can only have one instructor. There would be a constraint on the social security number ensuring that there are only nine numbers and in the format is xxx-xx-xxxx, and each individual number would be between 0 and 9. There would be a constraint for the telephone numbers as well. Each individual number would be between 0 and 9 in the format of (xxx)-xxx-xxxx.
Conceptual vs. Physical Model
The conceptual model will have all of the attributes from the students as well as the instructors. It will also have the all of the constraints. This model will have software and hardware independency. At this level any changes to the database management system will not affect this model. The physical model will take all the information that comes from the conceptual model and describe it so that it can be saved and stored. This model will need to know the physical storage device and access method so that it can reach the information stored in the devices. The physical model, not like the conceptual, will be both software and hardware