Re: Compiling after file changes -- MIDRANGE-L

Michael,

Two answers...

1) It often doesn't matter. Consider how many old style programs read
a input record once and never read it again.
2) If it does matter, include some "Time To live" (TTL) code in the
service program. So that after a period of time has elapsed, the
service program will reload the data. A small value, say 1-5 seconds
is usually all you need to eliminate redundant logical reads while
maintaining fresh data.

Charles

On Tue, Jun 1, 2010 at 9:24 AM, Schmidt, Mihael
<Mihael.Schmidt@xxxxxxxxxxx> wrote:

The problem with cached data is : when/how do you notice if they are out of date? ... just a thought (no response needed/expected).

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Charles Wilt
Sent: Tuesday, June 01, 2010 2:52 PM
To: Midrange Systems Technical Discussion
Subject: Re: Compiling after file changes

Yes, it could result in lots of _logical_ reads, since the page should
be in memory after the first read. But logical reads aren't nearly as
costly as physical ones.

Your service program could also check to see if it's already got the
data for the custom on-hand before reading it again.

You'd call other getters for the additional information you'd need for
the message.

If you find out that you often need the same group of fields, then you
could build a single getter that returns a DS (whose structure doesn't
change ;)

Charles

On Mon, May 31, 2010 at 3:49 AM, David FOXWELL <David.FOXWELL@xxxxxxxxx> wrote:

-----Message d'origine-----
De : midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] De la part de Charles Wilt

DO NOT SIMPLY CREATE GETTERS/SETTERS FOR EVERY FIELD!

Instead, have business logic routines that you can call.

Do this:

if CUSTOMER_IsOverCreditLimit(wCustomerNumber:wSaleAmount);
//display message?
endif;

Instead of this:
if wSaleAmount > CUSTOMER_GetCreditLimit(wCustomerNumber);
//display message?
endif;

Isn't that going to result in a load of file reads for the same customer? What if I other customer information must be used in the message?

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