RE: ODBC (was RE: Green screen - it's time is over )

["Joe Pluta" <joepluta@xxxxxxxxxxxxxxxxx>]

Walden, you asked to see a program that can be used to access a file.  This
does that.  The fact that it takes a shortcut for the message format isn't
relevant.  You seem to be missing the forest for the trees.

The example uses the physical layout of the file for the message base.  This
is simply a convenience.  Were the database layout to change, the message
layout could stay the same.  Of course, now I'd need a data structure
separate from the file, and I'd have to do moves, but I'm sure you
understand how easy that would be to implement.  Don't you?  It's really not
that difficult a concept.

There is business logic.  Please look again at the EDTDTA routine.  The
fields are edited for validity: for example, the customer name can't be
blank, you can't add duplicate records, and so on.  Yes, this is a simple
example.  It's for a rather trivial master file maintenance server.  But
still, anything more complex would simply involve expanding the EDTDA
subroutine.  Surely you see that, right?  Of course an order processing
server would get more complex.  But then again, an order entry program is
more complex than a customer maintenance program, no?

So, other than the fact that I have - for convenience - used the layout of
the physical file as my message layout, do you see how a CRUD server would
work?  I don't think I can ake example can be any clearer.

Joe

> -----Original Message-----
> From: Walden H. Leverich
>
>
> Joe,
>
> Unless I'm mistaken, the message format in this example is defined as the
> physical layout of the file. Your server programs are nothing more that
> wrappers around the CRUD functions. Where is the business logic? Take, for
> example, the idea of creating an order header, the business logic here
> involves, at a minimum, validating customer, ship to address, bill to
> address, getting the next order number, and returning that number to the
> caller. Even if you created yet another server side program to
> execute this
> business logic they'll be tied to the physical layout since the message
> layout is the physical layout, no?
>
> -Walden