Order Database – ER Diagram

Prepared by

Megan Foster

Fall Semester 2014

Step 1: Define Entity Classes and Primary Keys

Step 2: Define Relationships Among Entity Classes

Step 3: Define Attributes for each Table

Step 4: Create Database

Designing Databases with Entity Relationship Diagrams

Entity Class Primary Key

CUSTOMER Customer ID

ORDER Order ID

PRODUCT Product ID

ORDERITEM OrderID and ProductID

Step 1: Define Entity Classes and Primary Keys

Business Rules1. A customer can have unlimited orders.

2. A customer can have one order or have no order.

3. An order can only have one customer.

4. An order must have a product.

5. Orders must have one product

6. Many orders can have the same product.

7. A product can have multiple orders.

8. A product my have no orders.

Step 2: Define Relationships Among Entity Classes

CUSTOMER

PRODUCT

ORDER

ORDERITEM

Step 3: Define Attributes for each Table

Customer ID CustomerName PhoneNumber CustomerEmailCUSTOMER

OrderID CustomerName OrderDate

ORDER

OrderID ProductIDORDERITEM

ProductID ProductNamePRODUCT

Step 3: Define Attributes for each Table

CustomerID FirstName LastName EmailAddress Major

Location Gender

CUSTOMER

OrderID CustomerID OrderDate

ORDER

OrderID ProductID Quantity

ORDERITEM

ProductID ProductName Price BatchSize Description

Type

PRODUCT

List and Describe the Four Characteristics of a Relational Database.

1. Collection of Data2. Logical Structure3. Logical Ties (Foreign Key and Primary

Key)4. Integrity Constraints (Rules)

Step 4: Create Database

http://students.uwyo.edu/Mfoste21/IMGT2400/CowboyCookies.accdb