Re: COBOL400-L Digest, User Record Updates And Locking

["Stone, Joel" <Joel.Stone@xxxxxxxxxx>]

Thanks Chuck.

Just curious, what if the file being updated is a logical view with only 10% of the total fields in the record.  In that case, one would have to work with the PF just in case one of the non-visible fields was changed by another user?

Do shops take it to that level generally?

Thanks!


-----Original Message-----
From: COBOL400-L [mailto:cobol400-l-bounces@xxxxxxxxxxxx] On Behalf Of Chuck Landress
Sent: Friday, August 05, 2016 12:45 PM
To: cobol400-l@xxxxxxxxxxxx
Subject: Re: [COBOL400-L] COBOL400-L Digest, User Record Updates And Locking

Actually the procedure you describe is, in my opinion, the best way. You
avoid locking the record if the user has it on their screen for a long time
and you only update if a change has been made.

I worked on a system that read with no lock and then updated (COBOL can do
that). The number of inadvertent overwritten data changes was impressive.

​The system I work on currently locks records even on inquiries causing a
lot of system errors due to record locks. That said, we rarely have data
inadvertently overwritten. It sure is difficult to get the users to exit
screens before going to lunch.



--
Chuck Landress, PMP
678-469-2326

"Resistance is futile, you will be assimilated. We are the Bored"
-Unknown

On Fri, Aug 5, 2016 at 1:00 PM, <cobol400-l-request@xxxxxxxxxxxx> wrote:

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>    1.  user record updates via a cobol program: how to deal with
>       record locks and data changes (Stone, Joel)
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> ----------------------------------------------------------------------
>
> message: 1
> date: Fri, 5 Aug 2016 16:45:29 +0000
> from: "Stone, Joel" <Joel.Stone@xxxxxxxxxx>
> subject: [COBOL400-L] user record updates via a cobol program: how to
>         deal with record locks and data changes
>
> What is a good way to handle record locks when a user changes a DB record
> via a cobol pgm?
>
> Also how to avoid one user's changes from overlaying another user's recent
> changes.
>
> Is the best way to read with no lock, wait until user enters data into
> screen, then re-read with a record lock?
>
> And only update the record if there were no changes between the two reads
> by comparing the entire record strings?
>
>
> Any other methods that work well?
>
> Maybe read the journal to ensure no one else has changed that particular
> RRN during the users input?
>
> Thanks!
>
> Joel
>
>
>
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