Pathway/iTS TCP and Terminal Programming Guide

Designing Your Application
Compaq NonStop™ Pathway/iTS TCP and Terminal Programming Guide—426751-001
2-4
Identifying Transaction Components
Identifying Transaction Components
After you have identified the Enter Sales transaction for the order-processing
application, you list the functions performed by the transaction and group them either
into data collection and validation operations or into database update operations. For
example, the key functions performed by the Enter Sales transaction during data
collection and validation are:
•
Assembling information for the order header, including:
•
Obtaining the order-ID
•
Accepting the customer-ID
•
Accepting the requested delivery date
•
Accepting shipping instructions
•
Checking the customer-ID
•
Obtaining the customer’s name and address from the database
•
Assembling the order, including:
•
Accepting the list of order items and the quantity of each item
•
Checking the current quantity available for each item ordered
•
Accepting special instructions
•
Calculating total order cost
•
Obtaining the customer’s balance and credit limit from the database
•
Adding the total cost to the customer’s balance and ensuring that it does not
exceed the credit limit
The key function performed by the Enter Sales transaction during database update
operations is order completion. The order completion function includes:
•
Subtracting the quantity ordered from the current quantity available for each ordered
item
•
Adding the total order cost to the customer’s current account balance
•
Recording the order in the database
•
Recording the order invoice in the accounts receivable files
•
Recording order shipping information in the inventory files
The relationships of the various functions for the Enter Sales transaction are illustrated
in Figure 2-2
. The dark arrows in the figure show the sequence of actions from Step 1
through Step 3. The lighter arrows show the flow of information.