TMF Application Programmer's Guide (G06.24+)

HP NonStop TMF Application Programmer’s Guide—522419-004
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TMF Programming Environment
The Transaction Management Facility (TMF) provides protection and concurrency
control for HP NonStop SQL/MP and Enscribe files.
Database integrity is vital to the success of any online transaction processing (OLTP)
environment. It is imperative that data not become corrupted as the result of hardware
or software failures, or conflicting operations performed concurrently against the same
data.
TMF protects the integrity of your database against failure of any of the following:
•
A disk drive
•
A disk controller
•
A disk process
•
An application process
•
A CPU
•
An entire system
In addition, TMF provides locking mechanisms with which you can achieve various
levels of isolation from the effects of other concurrently running application processes.
As an integral part of the operating system, much of the TMF functionality is provided
by system components such as the file system and the DP2 disk process. From the
perspective of the application programmer, TMF and the protection it provides are
often entirely transparent.
This section contains the following topics:
Topic Page
The TMF Transaction
1-2
Heterogeneous Transaction Processing 1-5
The Requester/Server Model 1-6
The Current Transaction 1-7
Consistency and Concurrency 1-11