What is Business Programming?

["Nathan Andelin" <nandel@xxxxxxxxxxxxxxxxxxx>]

When Jeff asked this question my mind shifted to a program I wrote some
years ago, and is currently used by tellers in process sing over-the-counter
transactions at 250+ credit unions in the US.

A transaction begins simply enough by prompting the teller for:

Member Number
Account Suffix
Transaction Code
Amount
Description
Operation Code

Holy Cow, it would take a volume to describe the chain of events and
conditions those six (6) simple fields trigger.

Member Numbers uniquely identify credit union members, and properties
delineating conditions they've requested to be associated with their
accounts.

Account Suffix identify types of accounts which fall into three (3) general
classifications (shares, loans, and certificates of deposit), and
sub-classifications (savings, checking, individual retirement arrangements,
standard loans, credit card loans, etc.)

Transaction Codes identify types of transactions such as Deposits,
Withdrawals, Payments, Advances, Standard Debits and Credits, involving
various types currency, checks, and other mediums of exchange.

Transaction Amounts may be subject to dozens of conditions.

Operation Codes refer to external table entries that further qualify
transactions, and often lead to further prompts.  For example an Operation
Code may be set up for handling Traveler's Cheque sales, which need to
record the number, denominations, and serial numbers of cheques sold.

Teller user profiles themselves have numerous properties that affect program
flow.

Scanning the source code of this program, which is procedurally oriented,
gives a glimpse at the number of conditions, tables, and possible extensions
associated with every input field, which number in the hundreds.

Thank you, Joe Pluta, for pointing out that the strengths of OO are actually
weaknesses when it comes to handling procedures like this.  I strongly agree
with 90% of what you've written during the past several days.  You've taken
a lot of flack, and we're able to dish it back with remarkable agility and
clarity, focusing on specific issues.  

Nathan Andelin