Dear oh deary me, this is sooo 1970s!
Guys, Google 'optimistic locking'
[Quick overview:
1) When the user first looks at the data,
* read the record, no lock,
* save a copy in memory (Named Common) or on a BeforeLook disk file
2) When the user wants to update the record,
* read the record with lock
* compare the just-read record with the saved copy
+ if they are the same
- write the updates
+ if they are different
- give the user an error message
"someone else fritzed with it while you were dawdling"
* throw away the BeforeLook
* unlock everything, you're done
This is called 'optimistic' because you're betting that the BeforeLook
and the current record are almost always the same, so you hardly ever
get to take the error path.
End of quick and probably oversimplified overview]
-----Original Message-----
> From: u2-users-boun...@listserver.u2ug.org On Behalf Of Mecki
Foerthmann
> Sent: Thursday, 2 September 2010 5:00 a.m.
> To: U2 Users List
> Subject: Re: [U2] [UV] Shared Record Locks
>
>
> Bill,
>
> I thought doing something similar myself when I was a Junior
programmer
> because some people tend to lock records and go for lunch etc..
> But what happens if you read the record into the variable R.This do
some
> processing, then the phone rings and you talk for 10 minutes, while
> somebody else uses the same process, changes the record and writes it
>
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