BIS 245 Week
4 Lab – ER Diagram
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A. Lab # : BSBA BIS245A-4A
B. Lab 4A of 7: Database design based on data requirements and
business rules focusing on interpreting business rules to determine
relationships.
C. Lab Overview âScenario/Summary
TCO(s):
1. Given a business situation in which managers require
information from a database, determine, analyze and classify that information
so that reports can be designed to meet the requirements.
2. Given a situation containing entities, business rules, and data
requirements, create the conceptual model of the database using a database
modeling tool.
Scenario:
You have been asked to create a database model using MS Visio
Database Model Diagram Template. The purpose of this lab is to provide
experience designing, with limited instructions, a simple database based on a
list of data requirements and associated business rules.
Upon completing this lab, you will be able to
1. create a new Visio file for database design; and
2. using the data requirements and the business rules provided,
develop a conceptual model (ERD), including attribute data types and required
field lengths.
D. Deliverables
Section
Deliverable
Points
Step 6
YourNameLab4A.vsd (Visio Diagram)
E. Lab Steps
Preparation
1. Using Citrix for MS Visio and/or MS Access
a. If you are using the Citrix remote lab, follow the login
instructions located in the iLab tab in Course Home.
2. Start Visio
a. Open Microsoft Office 2010, Visio application, or
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b. if you are using Citrix, click on Microsoft Office 2010
Applications folder to start Visio.
Lab:
Step 1: Identify and create the entities
a. Open a new blank Database Model Diagram. If you need assitance
with this, refer to the Week 1 Lab Instructions. Be sure that all options are
set consistent to those used in previous weeks so that you generate your model
in Crows Foot notation.
b. Save the file as YourName_Lab4A.vsd.
c. Based on the information provided below, create the necessary
entities for the Catering by Caren database. If you need assistance to create
the entities, refer to Labs from Weeks 1 and 2.
Catering by Caren
Catering by Caren is an upscale catering company focusing on full,
four-course gourmet dinners for groups from two to forty. Owner/chef James
Caren is wonderful in the kitchen, but has become overwhelmed with the business
side of running his rapidly growing operation. You have been hired as his
business manager, and youâve decided to computerize information on the
engagements.
Chef Caren is excited about this project and has provided you with
the following information. He doesnât know databases nearly as well as he knows
haute cuisine, so the data requirements are not well-organized, nor is data in
its smallest parts. He has noted whether the menu items are appetizers, salads,
main courses, or desserts. He has also provided a list of the information he
keeps on each customer and each booking.
By talking with Chef Caren, you feel you have enough information
on the companyâs business rules to understand the relationships between the
data. Chef Caren is particularly concerned that you capture the exact
requirements for the menu for each engagement. For instance, if 20 people are
to be served, he wants to know how many want the vegetarian main course, the
Kosher meals, and so forth.
At this point, you are going to use the following information to
put together an entity relationship diagram that you will then use with Chef
Caren to verify that you have accurately captured the requirements.
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Customers
Name
Phone
Address
E-mail Address
Approved for credit or not
Engagements
Date
Time
Location
Menu
Number of Attendees
Special Diet Plates
Assistant Chef Assigned
Employees Assigned
Payment Method (AmEx, Visa, MasterCard, Check, Cash, Bill)
Deposit Amount
Deposit Paid Date
Total Charges
Balance Paid Date
Menu Items
Item Name
Description
Classification (Appetizer, Salad, Main Course, Dessert)
Special Diet Item (Kosher, Vegetarian)
Employees
Name
Position
NOTE: You may find it helpful to consider the business rules in
Step 4 in creating your entities.
Step 2: Identify and create attributes (fields)
NOTE: Because you are creating your diagram in Visio, it will be
easier to create the attributes prior to the relationships.
a. Refer to the data requirements from Step 1 of this lab. If you
have not already
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created the attributes (fields) in your ERD, add them at this
time.
b. Save your file and continue to Step 3.
Step 3: Identify and designate the keys
a. Detemine whether an attribute exists in each table that will
satisfy the requirements of a primary key. If no appropriate field exists,
create a field for this purpose.
b. Check the Primary Key property for the field(s) in each table
using the Visio column properties.
Step 4: Identify the relationships
a. Using the information below on the business rules for Catering
by Caren, create the relationships between the entities created in Steps 1 and
2.
b. Notice that, where Many-to-Many relationships exist, you will
need to create associative entities. If you are not sure of the process to
create relationships in Visio, refer to the Labs for Weeks 1 and 2. You created
an associative entity in Week 2.
c. For any associative entities created, enter necessary fields.
You may also need to designate or create a primary key. NOTE: If the
relationship is mandatory (must have at least oneâ¦) you will go to the
relationship Miscellaneous property and change it from Zero to Many to One to
Many.
BUSINESS RULES
Business rules help determine the relationships between data that
should help you design the relationships between your entities.
1. Each customer can book many engagements over time, but each
engagement is placed by only one customer.
2. One assistant chef is assigned to each engagement. An assistant
chef may work many engagements over time, but each engagement will have only
one assistant chef assigned.
3. Each engagement will have many menu items. Each menu item may
be served at many engagements. When a menu item is selected, the number of
servings required for the event must be recorded. (Hint: Remember that an
associative entity may have attributes!)
4. Each engagement must have at least one assistant chef assigned.
There may be many other employees assigned to the engagement. Each employee may
work many engagements. However, some employees never work engagements.
5. Only one engagement may be scheduled for any particular date
and time.
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Step 5: Determine and specify the data types
a. Using the information below select the data type for each
attribute (field) in your diagram, and set the type in the attribute
properties. (Refer to the Week 2 Lab if you are not sure how to do this. Where
allowed, estimate the field length needed.)
As the data types and field lengths are not included in the data
requirements, you should make a selection based on your knowledge of the type
of data and approximation of length required. The Visio equivalents are shown
below
Access
Visio
Number
Integer
Text
Text
Memo
LongText
Date/Time
DateTime
Currency
Currency
Yes/No
Binary
AutoNumber
Long
Hyperlink
No equivalentâuse Text
Step 6: Modify the Visio Settings to show the Data type and field
size in the diagram.
a. Change your Visio settings so that the data type and field size
appear on the actual diagram. If you are unsure of the steps to do this, refer
to the Week 3 Lab.
b. Be sure to save the final version of your file.