Introduction to Data Management

Developing Applications With PATHWAY
6-2 15873 Tandem Computers Incorporated
Figure 6-1. Requester and Server in a PATHWAY Application
S8020-031
• • •
Display
Screens
Requester
Server
Database
Accept
Commands
and Data
Return
Replies
Read
Records
Send
Requests
Write
Records
Order Entry
1. Display blank order screen.
2. Accept new order data.
3. Send data to server for verification and totals.
12. Display completed order screen.
13. Accept order confirmation.
14. Send data to server for database update.
18. Display blank order screen
(with successful update message).
Terminal Management
4. Get request message.
5. Get new order number.
6. Verify state code.
7. Verify card code.
8. Check stock level.
9. Calculate order totals.
10. Check credit.
11. Reply with completed order data.
15. Get request message.
16. Update database with order data.
17. Reply with successful update code.
Database Management
Requester-Server Application
Codes
Stock
Orders
PATHWAY requesters run screen programs that control displays on I/O devices and
processes, accept requests and data from these devices and processes, and transmit
these requests to servers. You write these screen programs in the SCREEN COBOL
language, which is very similar to standard COBOL. You can write your servers in
COBOL85 or COBOL 74, as well as in other languages. So, if you know the COBOL
language, you will find it easy to write a PATHWAY application even if you do not
use PATHMAKER.