Re: In defense of the lowly MR

John,
Your points are well taken within the limits of information I provided.

Naturally the complete data base structure is more complex than the
example given.

During the delete process we determine if anyone else has the customer
or any children on screen and ask the user requesting the delete if a
data queued delayed delete would be acceptable to them.

John Earl wrote:
> 
> Hi Jim,
> 
> I have a number of disagreements with this approach.  You've thrown the bait
> out, now I think I'll bite.   :)

Thanks :)

> The computing public has come to expect real-time databases, and by not
> deleting children records you run the risk of serving your users dirty data.

By using joined master, childern logicals, the orphaned children are
excluded and do not provide misleading hash totals.  "Real-time" is a
perception of data presentation, not necessarily of data retainage.
> 
> Better to have a last changed date/time/user stamp on the record so that you 
>can perform a manual
> "rollback" of all records whose last change date matches the parent.

Not a bad idea, we then could then use the trigger program approach and
not worry about users not using the joined logicals for an queries they
may write.
> 
> No need to lock a record that you're not prepared to change immently.  As
> long as you don't lock on every read, locks are nothing to be afraid of.

I believe by nature a UP processed file would lock each record as it
went.
> 
> But what it really comes down to is that MR is a kluge that was required
> when RPG worked over primitive databases.  Now through the use of RDB's with
> better views, joins, triggers, and stored procedures, there's no reason to
> do in RPG what the database was designed to do.  If it's the job of the
> database to do, leave RPG out of it.

I agree wholeheartedly...the "soundness" of a system is enhanced
greatly.  Now if I can convince all of the users to dump their existing
data bases......

Best regards,
-- 
===================================================
James W. Kilgore   | Progressive Data Systems, Inc.
President          | 311 31st Ave SE
(206) 848-2567     | Puyallup, Washington 98374 USA
qappdsn@ibm.net    | http://www.ultimate.org/PDS
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