1. :Exercise
Precision Tools sells a line of high-quality woodworking
tools. When customers place orders on the company’s
Web site, the system checks to see if the items are in
stock, issues a status message to the customer, and
generates a shipping order to the warehouse, which fills the
order. When the order is shipped, the customer is billed.
.The system also produces various reports
Draw a context diagram for the order system •
Draw DFD diagram 0 for the order system •

2. Context
Diagram of
Order
System

3. Level-0 of
Order
System

4. Perfect Pizza wants to install a system to record orders •
for pizza and chicken wings. When regular customers
call Perfect Pizza on the phone, their phone number
goes automatically into the Pizza system. The phone
number invokes the name, address, and last order date
comes automatically up on the screen. Once the order is
taken, the total, including tax and delivery, is calculated.
Then the order is given to the cook. A receipt is printed.
Occasionally, special offer (coupons) is printed so the
customer can get a discount. Drivers who make
deliveries give customers a copy of the receipt and
coupon (if any). Weekly totals are kept for comparison
. with last year’s performance
Draw a context diagram for Perfect Pizza •
Explode the context-level diagram showing all the major •
. processes

5. Another Example
Perfect Pizza: Context Level Diagram
Weekly
Report
Phone Number
Customer
Customer Order
Delivery
Person
Delivery
Information
Customer Info
Management
0
Customer
Order
System
Cook Order
Cook

6. Another Example
Perfect Pizza: Current Logical Level 0 Diagram
Customer Order
Customer
Phone
Number
1.0
Find
Customer
Record
Customer
Info
Customer
Information
Customer
Record
2.0
Take
Customer
Order
Order
Information
Customer
History
Order
Information
D2 Customer History
D1 Customer Master
Customer
Record
5.0
Add
Customer
Record
3.0
Print
Delivery
Order
D3
Sales Records
Sales Info
Weekly Report
Management
7.0
Print
Weekly
Totals
Delivery
Information
Delivery
Person
Discount
Info
6.0
Send
Order
to Cook
Cook
Order
Cook
Customer Customer
Order

7. Another Example
Perfect Pizza: Current Logical Child Diagram
Customer
History
Order
Information
3.1
Determine
Customer
Discount
D2 Customer History
Customer
Information
3.2
Record
Discount
Discount
Amount
3.3
Print
Delivery
Instructions
Delivery
Information
Discount
Information
D3
Sales Records

8. Another Example
Perfect Pizza: Current Logical Child Diagram
Customer Information
5.1
Record
Customer
Information
Raw
Customer
Information
5.2
Store
Customer
Record
Customer
Record
D1 Customer Master