Re: In defense of the lowly MR

[Buck Calabro <mcalabro@xxxxxxxxxxxx>]

>>> 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..
>
>The problem is; you (we) are no longer the sole arbiter of data
>presentation.  Data users now have query tools, ODBC, file transfer, etc..
>The data you once gaurded so jealously can now be strewn across a far-flung
>network of disparate systems where your presentation techniques are not
>acknowledged.  No, the database has to contain the whole "truth", and not
>rely on clever programming in order to be interpretted correctly..

I'm 100% in agreement here.  Well said!

>>> 
>>> 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..
>
>Then why use UP?  Better to use IF and UF versions of the same file, and
>only read records with the IF version until precisely before you're ready to
>update.  You have no way to prevent a user from bringing a record up on
>screen and then running off to a two hour meeting, but you can, and should,
>prevent them from holding a record lock for that two hours..
>
>JMHO, of course..

UP files work very well for batch jobs, where by definition you can't lock a 
record for a long time.  I'd never consider UP for interactive work.  I'd 
rather use UF with a CHAIN (no lock) for the "get" part of the app, then CHAIN 
(lock) for the "update" part.  Now, of course, we have the "record changed in 
the interim" problem to contend with...

Buck Calabro
Commsoft
mcalabro@commsoft.net
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