Re: check for record changed between read/chain(n) and update

["Gene Burns" <burns.gene@xxxxxxxxx>]

How are you defining Record?  You stated that Record has the new values.
Are you working with the subfields in the DS or the fields in the file that
have the same name?

When I do chain(n) clmmas mstr the subfields of Ds mstr are populated but
the file fields accessed in the program are empty.  This is why I did a
second chain, to access these fields as field1 instead of mstr.field1



On 6/5/07, Booth Martin <booth@xxxxxxxxxxxx> wrote:
> What I do is have three data structures named "Record", "OriginalRecord"
> and "NewRecord", all defined like the record format.  Then I prefix two
> of the data structures as  "O_" & "N_"   Then, on the original read I
> eval OriginalRecord = Record.
> Then, later just before I do the locking read I move the Record (which
> now has the new values) into NewRecord,
> If NewRecord = Original then there are no proposed changes, so bail out.
> Otherwise do the locking read and again compare the Record to Original
> Record.
> If the Original is *not* equal to the Record then there have been
> changes at another workstation, do as is appropriate to the business
> rules.
> If the Original is equal to the Record then its is safe to make the
> change, so eval Record = NewRecord and do the update.
>
> Seems to work fast and is really handy if you also are using F5=Refresh
> (Record = OriginalRecord) to let the user undo changes and start over.
>
>
>
> Gene Burns wrote:
> > I need to change a program to get a record from a file chain(n) and let
> the
> > user work with the data, go to other programs, return to the original
> > calling program, etc., then if the user makes changes to the data I need
> to
> > check whether the record has changed before updating.
> >
> > Is there a better way to do this than bringing the data record into a
> data
> > structure chain(key) file DSname and then rewriting the entire program
> to
> > use the qualified field names from the DS?
> >
> > I am concerned that even if I do this, that the record could be updated
> in
> > between the chain to get the record into a DS for comparison to the
> original
> > DS and the actual update.
> >
> > Gene
> >
>
> --
> ---------------------------------
> Booth Martin
> http://www.Martinvt.com
> ---------------------------------
>
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