Re: Business objects, subset of collection

Responding to Frebe...

By the way, what is your RAD IDE of choice?
For the last 20 years before retiring I was an R-T/E guy so the only RAD
problems we saw were support tools for the software process (e.g.,
defect tracking). For that mundane stuff I usually used Access. I
haven't looked at the market so I wouldn't know what to use for
something like a web-based POS where one has both networking and server
issues. (There wasn't much around back in the '70s when I was doing IT,
but I'm sure we've come a long way since.)
When you say "When I need to solve a CRUD/USER problem I forget about
OO and use a RAD IDE", you are talking about MS Access? Since you
frequently refer to RAD IDE as the silver bullet for everything that
the OO model can't solve, it is a little big surprisingly that the
only RAD IDE you have experience from is MS Access. Don't you think
there are something between the OO approach and MS Access?
To clarify, when I refer to RAD IDE I also include the object-based
"canned" infrastructures in things like .NET and J2EE that support the
1D Presentation/Business/Data models. Those are certainly between Access
and an OO development.

In what way does J2EE support 1D Presentation/Business/Data?

I forget the buzzwords because I don;t do Java, but it supports the equivalent of MS' DAO and whatnot.


create view invoice_balance as
select i.invoiceid, i.amount - sum(p.amount)
from payment p
join invoice i on i.invoiceid=p.invoiceid
group by i.invoiceid
How is this different than a VBA routine tied to a predefined event in
Access and stored by Access for reuse?

If you show the VBA routine, I can tell the difference...

The only difference is the syntax details.

The VBA syntax will be very
similar since it is designed (i.e., has specialized constructs) to be
compatible with and easily converted to SQL.

Are you saying that Visual Basic and SQL has similar syntax? If yes,
please show it to me.

VBA has similar syntax to SQL for queries and table access. But you are pulling a Topmind and deflecting onto a tangent that has nothing to do with the thread.


Using such view, you call "select balance from invoice_balance where
invoiceid=?", whereever in your application, reusing the business
logic above.
I am missing the point. This seems like basic modularization that goes
bas to function libraries under SA/D/P. Different development
environments will have different mechanisms, but they all do the same
thing. (The OOP-based agile processes argue that the primary goal of
refactoring is to eliminate code duplication and ensure reuse.)

Yes, you almost got it. Views corresponds to functions or classes. It
is all about modularization.

But what is the point in this context? Almost all 3GLs have the ability to encode procedures and the ability to reuse those procedures. What has that got to do with CRUD/USER processing and RAD IDEs?


--
There is nothing wrong with me that could
not be cured by a capful of Drano.

H. S. Lahman
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