TMF Introduction (G06.26+)

TMF Application Programming
HP NonStop TMF Introduction—522414-002
5-14
Developing Servers for Database Access
A typical sequence of SCREEN COBOL actions for a long transaction is shown in
Figure 5-5.
Advantages of long transactions are:
•
Context is minimized because the requester does not collect all input at once.
•
Failure at any point during the TMF transaction causes all updates to audited data
to be backed out.
Figure 5-5. A Long Transaction
Server
Server
Server
Database
Transaction State
ACCEPT data
•
•
•
BEGIN-TRANSACTION
•
•
•
SEND to server
•
•
•
ACCEPT data
•
•
•
SEND to server
•
•
•
ACCEPT data
•
•
•
SEND to server
•
•
•
END-TRANSACTION
Requester
Operator
Action
Display 1
Display 2
Display 3
Operator
Action
Operator
Action
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