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

----- Original Message -----
From: <thomas@inorbit.com>
To: <midrange-l@midrange.com>
Sent: Friday, November 16, 2001 10:34 PM
Subject: ODBC (was RE: Green screen - it's time is over )


> Joe:
>
> On Tue, 13 November 2001, "Joe Pluta" wrote:
>
> > ODBC, no matter what the application, goes against every
possible tenet of
> > distributed processing.  It is slow, and it ties your host
database to your
> > client code.  You cannot change even the names of your columns
(much less
> > the physical layout and location of your data) without
updating your client
> > code.  This is absolutely unacceptable.

I was about to ask if anyone has used other ODBC or OLEDB drivers
besides IBMs, and what the speed etc. looked like with them.

I don't know what language you are connecting to ODBC with, but
with VB6 (and earlier versions) you can:

Create new tables, columns, indexes
Populate the rows with data
Delete and modify column structures
Run most any sort of sql
Create stored procedures
Execute stored procedures with parameters
And most importantly,
    understand what is going on when you read the code

And it doesn't take a recompile to modify the structure.

Of course, I don't know if IBMs ODBC driver supports this, I
haven't tried it yet.

I have no idea why you would want to change the names of columns,
I would think that would be very poor programming practice, if you
mean the names of columns in tables. It will sure be a surprise to
the other people trying to access the database if you do.

The physical layout of your data? Do you mean the order of the
columns in the table? What would the purpose be for doing this?
Are you referring to physical files and members, library location
and so forth?

I've gotten the rough impression that the Java access to the 400
thru the jar is a lot faster and better than the VB access. It
would be nice, if this is so, if someone would write some kind of
wrapper so those functions could be accessed from VB. It would
sure speed up development for some of us. There are a lot of VB
coders out there, and there are a lot of nifty add on controls for
VB that are well integrated to the Windows environment. Java seems
more like a religion than a programming language to me.

Part of my problem is I've been programming too long - machine
language, then Fortran, Basic, Assembler, COBOL, more Assembler, a
little Pascal ( the language designed to keep you from controlling
the computer unless you violate its strictures - which everyone
does) more Assembler, then VB.

I remember reading books on C and thinking, how clever to do it
this way, but why do you want to confuse the people coming behind
you who have to clean up the mess?

And Java frankly looks like more of the same. Beans and jars and
swishes (I can't remember the name of the latest cutesy thing, I
assume it is another sort of library structure). Too much of that
sort of thinking and you end up programming with half a mouse.

I think of Java and C as wonderful things for writing middleware.
Maybe.

I understand that with Java you can write programs that will run
on the HP 3000 and VAX and Data General, and all those other
machines that just evaporated into the mists of time.

I've just started learning RPG/400 from a book. ( I know, now you
call it something else.)  I don't intend to use it for development
myself (I've got guys at the office who do that) but I wanted to
have some understanding of it. I can see it started out as am
assembler-style program generator, where you didn't have to write
the basic cycle logic.

We used to laugh, in the early days of the structured programming
fad, about the implementation of the 'COME FROM' to replace the
'GO TO'. It looks like RPG has this designed in - you set an
indicator and suddenly you aren't in Kansas anymore. Just eyescan
a couple of thousand lines to find out where you end up, I guess.
I won't ask if I am missing something, I am sure I am.

I love the LEAVE command. I heard that mentioned on this list and
I thought -wow- I wonder if that means just wander off? I have had
programs do that but I didn't think anybody would design it into
the language. I discovered today that it is an EXIT DO. VB doesn't
have an ITER command (although a well structured program in VB
would use IF/else/end if or SELECT/CASE/END SELECT to avoid the
need for it).

Is anybody writing new programs in RPG? Are they just maintenance
programs and add-ons? Is anyone writing new systems in RPG? I
can't imagine you are. I've seen another discussion group where
they are using some tool to write CGI programs in RPG, and the
arcane discussions they are having about that are astounding.

I think it would be pretty easy to write and compile VB program to
talk dataqueues to an RPG server program, so you could do the form
processing in VB where it is easy, and just pass data back and
forth to the RPG program. Even that is not quite what I would
like. What I would really like is to invoke a new copy of the
server program for each browser session, so the server can be
written single-threaded (it doesn't have to keep transaction state
for N clients, in other words).

I've got no idea if that is possible - or what would happen to the
AS/400 if you had a hundred or five hundred copies of a
fill-out-the-form program running - particularly if they start and
stop.  I suppose you could start them up as you need them and
leave them running until there has been no demand for that copy
for x minutes.

The compiled VB DLL would be designed to run in the Microsoft ASP
model - which has been fast and scalable for us. I'm talking about
one DLL that would be used by all RPG customers, not changing the
VB code for each RPG program.


Brad Jensen
Electronic Storage Corporation