Nathan
I don't really know what point it is you are making, but it seems to me you
are promoting the use of business objects. Personally I fully advocate their
use (and agree with Walden, disagree with Joe). The benefits in performance,
scalability and developer productivity are real and easily recognised and
very real.
Maurice O'Prey
-----Original Message-----
From: web400-bounces@xxxxxxxxxxxx [mailto:web400-bounces@xxxxxxxxxxxx] On
Behalf Of Nathan Andelin
Sent: 08 July 2008 16:05
To: Web Enabling the AS400 / iSeries
Subject: Re: [WEB400] Mapping SQL Result Sets to Browsers
From: Joe Pluta
this sort of (programmer) performance gain very easily translates
into performance LOSS for the user. In the above situation, let's
take the calculation. Is it performed when the Item object is loaded?
Or when the property is requested?
I've been considering that question. Particularly as it relates to
"available balance" in bank accounts, which is a calculated value. And the
algorithm can be quite complex. Holds of various amounts may be in effect,
and may have various durations, and come from various sources (questionable
deposits from questionable sources, loan collateral, minimum balance
requirements, scheduled withdrawals, etc.).
In the former case it will be calculated and often never used, while
in the latter case it will be calculated over and over again.
And back to the banking application "available balance" may be calculated
one way when the customer is viewing the account over the Internet or
standing in front of the teller window, but calculated another way when a
batch process is clearing checks or automated loan payments or ACH
transactions, or automated transfers, or ATM transactions, or debit card
transactions from merchants, where overdraft protection may or may not come
into play.
Available balance may calculated differently based on type of account
(Checking, Savings, IRA, SEP, Certificates of Deposit, Credit Card, etc.)
I guess the point, is that you may need to plan for a lot of flexibility,
and change as business rules change.
Nathan.
midrange.com
