Re: SQL and commitment control

If you are adding to an existing system that has not implemented controls
for this then you face a large uphill battle.

There are many methods that could be used to control this such as using
status codes on the header file to indicate the purchase order is still
being created, you may also need these codes on the detail file if any
programs go direct to the details without retrieving the header.

This also needs soft locks for the user that gets half way through and
then uses the red X to exit - one method for this is to have a locks file
where as an example only the unique purchase order number is written out
and then retrieved with lock. Recovery is then a procedure that can be
run that checks for any incomplete purchase orders and the lock record not
locked.

Another option that I like is to use intermediary files which hold the
transactions and not until the, in this example purchase order is complete
then the update/create procedure is run. I like this as it does not
matter where the transactions are initiated from the same update (and
revalidation) process is call to post the transaction.

Just my two cents

Happy New Year


Don Brown




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