Question: #1221

You have been hired by an environmental consulting company CC Complete Solution

Exam No. 1, (Take-home part,  70%)

Copy each question before answering it ( 6 questions in total).

1. (12 points) You have been hired by an environmental consulting company (CC) that specializes in creating environmental impact statement (EIS) for large projects. It needs a database to track the progress of each EIS. The company is particularly concerned about tracking public comments, questions from state and federal officials and the response to all these comments. All comments are scanned and stored as digital files.

Create a data model (E/R model) for the database based on following report.

EIC project #:

Date initiated:

Date ECC involved

Date ECC finished

Client

Principle contact:  Billing:

Phone:  Phone:

Contact address  Billing address

City, state, zip  City, State, Zip

Site location:  latitude  longitude

Site address :  city  state  zip

 Site description

Proposed  development description

Proposed activities (standard list)

Drain wetlands

Fill

Build road

Store waste

Comments and response

Date received Category      Source  File  Response date  Person  title

…m m m < /span>

2 (15 points) You are asked to develop a database for microcomputer lab management. You want to keep track of the following information (Type your answer):

The information about computer  such as station ID, vendor, model, etc.

The information about the software installed. Each computer is equipped with various types of software (e.g., word processor, spreadsheet, database, Web page tools, etc.) Note you only care about the types, version and vendors of the software, not the licensing information of each piece of software. You just want to know which type of the software is used most frequently.

The information about projects that are running on some computer systems (hardware). Including the project ID, description, project leader and starting date, etc.

The information about users who are the employees currently working some projects. Including emplyee’s  ID and name, as well as job title.

The information about appointments made by users to use the lab. For an appointment, employee must indicate the computer (station ID), types of software, and the time period of using computers.

Note:   In each appointment, an employee can only indicate one computer with multiple software to use.

a.  Design an E/R diagram to describe above situation.   

b.  Convert the data model in (a) into database design model, showing the keys, attributes, foreign keys. Use table notation (Tablename (....)).

 3.   (15 points) Given a table (and assuming the given data shows all possible FDs.)

playerID

name

year

JerseyNo.

scoreInYr

gamePlayed

teamID

teamName

teamLoc

TeamManager

1

john

2001

32

150

5

1

xyz

LA

lee

1

john

2002

32

140

6

1

xyz

LA

smith

2

Roman

2001

10

120

1

2

abc

NY

kim

3

shaw

1999

10

120

1

3

ijk

NY

kelly

3

shaw

2001

10

110

2

1

xyz

LA

lee

3

shaw

2002

11

130

2

3

ijk

NY

kelly

4

peter

2001

15

140

2

2

abc

NY

kim

……
Type your answer

 a.  List all FDs. 

 b. If you want to create above table in a database, what is the primary KEY for this table? (note this table is in a very bad design).

 c. What normal form this table is in? Why ?

d. Describe the insertion,deletion and update anomalies, be as specific as possibel. For example, you need to say, when row X is deleted because of player W quit the job, then we need to deleted what  row, and what problem will occur. etc.

 e. How many themes (i.e., pieces of information) that are implied by above table?

 f. Normalize above table into 3NF. In the normalization result you must show the table name and the key,and FK if there is any.

 

4. (10 points) A  law firm designed the following table to keep track the information  about cases and the lawyers who handle the cases:

Case (caseNumber, caseDescription, lawyerInCharge, caseAssistant, beginningdate, ending,Date, lawyerRate, accumulatedHours, clientsName., clientPhone, clientAdress, clientType, laywerPhone, caseResultDescription, clientCurrentPayment, paymentMethod, salary, bonus)

Among above attributes,

caseNumber, is the ID of the case

lawyerInCharge is the name of the lawyer (a single person) who in charge of the case.

There may be also several other people in the firm serve in the same case as the caseAssistant working for one lawyerInCharge

beginningDate, ending,Date indicate the period of the case

lawyerRate, is the hourly payrate of the client have to pay for the firm’s service in this case. This rate depends on the case.

accumulatedHours is the total hours of the client service,  

clientType can be either individual or cooporate,

laywerPhone is the phone number of the lawyerInCharge,

caseResultDescription gives the description about the case result.

clientCurrentPayment shows the total payment from client

paymentMethod can be credit card, cash or check

salary and bonus belongs to the lawyerInCharge 

Type your answer

 

a. List all functional dependencies based on the given information

b. What is the key if you have all these attributes in just one table?

c. How do you normalize the table into BCNF. Show your result. (don’t forget the table name and the key for each table. Also pay attention to the foreign keys).

 

5. (12 points) Use the following form given by Chen's Art Gallery

Gallery Customer History Form

Customer Name 

                  Jackson, Elizabeth                          Phone  (206) 284-6783

123 –4th Avenue

NoOneLivesIn, NJ00001

 Purchases Made

Artist                                     Title                                                      Purchase Date                  Sales Price

03 - Carol Channing         Laugh with Teeth                            09/17/2000                        7000.00

15 - Dennis Frings             South toward Emerald Sea         05/11/2000                        1800.00

03 - Carol Channing  At the Movies                                           02/14/2002                        5550.00

15 - Dennis Frings             South toward Emerald Sea         07/15/2003                        2200.00

The Chen's Art Gallery wishes to maintain data on their customers, artists and paintings.  They may have several paintings by each artist in the gallery at one time.  Paintings may be bought and sold several times. In other words, the gallery may sell a painting, then buy it back at a later date and sell it to another customer.

 a. Create an E/R model for this information requirement.

b.Transform the E/R model into a set of tables that are at least in 3NF.

6.  (6 points) What is denormalization?  Why is it necessary sometimes. Give an example (not from the book) with your explanation.  

Solution: #1218

You have been hired by an environmental consulting company (CC) Complete Solution

Computer (StationID, Vendor, Model)

Software (SoftwareID, Type, Version)

SoftwareInstalled (SoftwareID, StationID)

Vendors (VendorID, Details)

SoftwareVendors (SoftwareID, Ven...

Tutormaster
Rating: A+ Purchased: 11 x Posted By: Vikas
Comments
Posted by: Vikas

Online Users