Week 1 Discussion Entities and Attributes

You have been tasked to create a database for your college to track students, their courses (past, present, and future), grades and academic standing, and instructors.

Describe the entities and their attributes that might be required for this application, the type of database processing required, and the application software needed.

Consider all users of the application and how the issues of data integrity, security, and user interfaces would best be handled.

I believe the type of database processing required for this system is relational database because RDB is suited to manage constructive data which requires concurrency and data consistency.

In designing a relational database, each relation needs to be an one-to-many connection. Therefore, I created Enrolled Courses entity between Students entity and Courses entity, and Student Degree Plans entity between Students entity and Academic Disciplines entity in which academic majors and minors are defined.

CMIS320_W1_ERM.png

Since the system is simple and small scale, Microsoft Access is enough to start.

Homework1

Consider a student club or organization in which you are a member. What are the data entities of this enterprise? List and define each entity. Then, develop an enterprise data model showing these entities and important relationships between them.

fileCMIS320_Homework1.pdf

Week2 Relational Model and an Introduction to SQL

Answer just one of the following questions. Be sure to read other student posts and work to not duplicate information that has already been provided.

1) What is Dr. Codd's relational model and what does it include

2) Contrast the terms relation, tuple, and attribute with table, row, and column.

3) Describe the relationship between a superkey, a candidate key, and a primary key. Give an example.

4) Explain where you can use business rules in an organization.

5) Describe and give an example of one of the following:

3) Describe the relationship between a superkey, a candidate key, and a primary key. Give an example.

A super key of a relation is an attribute or a subset of attributes which identify a unique tuple.

A candidate key of a relation is one of super keys which is a minimal set of attributes to identify a specific tuple. This key name is derived from a candidate for a primary key.

A primary key of a relation is a candidate key which is the best to identify a tuple. The values of this key are required to be unique for each tuple in a relation.

For example, when there are multiple attributes named City ID, City name, County name, and State name in a relation for cities of United States, All of City ID, the subset {City ID, City name}, the subset {City ID, State name}, the subset {City ID, City name, County name, State name}, and the subset {City name, County name, State name} are super keys. On the other hand, Candidate keys in this relation are City ID and the subset {City name, State name}. Either City ID or the subset {City name, State name} can be the primary key. If you set City ID as the primary key, the subset {City name, State name} would be an alternate key.

Homework2

For each of the following descriptions:

a. A piano manufacturer wants to track all pianos it makes. Each piano has a unique serial number and a manufacturing completion date. Each instrument represents exactly one piano model, all of which have an identification number and model. The company produces thousands of pianos of a certain model, and the design is specified before any single piano exists.

b. A vendor builds multiple types of tablet computers. Each has a type identification number and a name. The key specifications for each type include amount of storage and display type. The company uses multiple processor types, exactly one of which is used for a specific tablet type. The same processor can be used in multiple types of tablets. Each processor has a manufacturer and a manufacturer's unique code that identifies it.

perform the following tasks:

1. Identify the degree and cardinalities of the relationship. 2. Express the relationships graphically with an E-R diagram.

Document your work into a single, well-organized, well-written word document and submit no later than due date.

fileCMIS320_Homework2.pdf

Week3 Enhanced E-R model discussion

Provide your own unique example of a supertype/subtype relationship. Be sure to describe the relationship and discuss if the disjoint or overlap rule would apply to your example.

Homework3

You are working for country club with thousands of members. You have been tasked with designing a database to keep track of the members and their guests.

The club keeps track of mail and telephone contact information, name and membership number. When a member joins the club they can become a social member with pool, racket ball and weight room privilieges or golf member which includes all of the social member privileges plus access to the golf course.

Develop, document and design an EER for this situation.

Submit your word document no later than the due date.


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