#contents

//** Week 1 Introduction
//
//- Question
//
//Introduce yourself here by telling us your name, what part of the world you live, your major or primary area of study at UMUC and what you envision doing with your programming skills you obtain from this course.
//
//- Answer
//
//Hello everyone, my name is Yuji Shimojo and I'm 27. I am from Okinawa, Japan and live there now. I'm in charge of presales of cloud systems integration and application development at an IT company based in Okinawa. Actually, I used to study Information Engineering at University of the Ryukyus in Okinawa, but I dropped out of the college 5 years ago. While in the college, I had lived in San Jose, California for 6 months for an internship. I'm currently majoring in Computer Science with a minor in Business Administration. I took CMIS242, CMSC335, CMSC350, CMSC325, CMSC330, CMSC412, and CMIS330 as part of my major in the past. I would like to improve my database systems architecting skills to enhance my sales engineer career this course.
//
//In my spare time, I enjoy traveling. I've been to California, Taiwan, and several places in Japan. I especially like Taiwan because it is very near from my place. So far I went there 5 times.
//
//I also enjoy scuba diving. Okinawa is known as one of the best islands for scuba diving, so you can enjoy all year round!

** Week 1 Discussion Entities and Attributes [#pa7da807]

- Question

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.

- Answer

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.

#ref(CMIS320_W1_ERM.png,,90%)

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

** Homework1 [#dfacf0ef]

- Question

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.

- Answer

#ref(CMIS320_Homework1.pdf)

** Week2 Relational Model and an Introduction to SQL [#m91d8575]

- Question

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:

-- derived attribute
-- multivalued attribute
-- ternary relationship
-- required attribute

- Answer

''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 [#l4f5e909]

- Question

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 hs 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.
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.

- Answer
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