RE: Single record access really required (was RE: Views and Index es)

[CWilt@xxxxxxxxxxxx]

> -----Original Message-----
> From: Joe Pluta [mailto:joepluta@xxxxxxxxxxxxxxxxx]
> Sent: Tuesday, July 27, 2004 11:27 AM
> To: 'Midrange Systems Technical Discussion'
> Subject: RE: Single record access really required (was RE: 
> Views and Indexes)
> 
> 
> > From: CWilt@xxxxxxxxxxxx
> > 
> > I guess I don't get it Joe.
> > 
> > All your user screens and inquiries can only handle a 
> single item at a
> > time?
> > 
> > If you've got an "Add item by item number screen", there's only a
> single
> > input line and the user hits enter for every item?
> > 
> > Well, ok then if that the limit of your software then I guess native
> I/O
> > is the thing to use.
> 
> Okay, Charles, please show me the code that would allow you to loop
> through the subfile using an SQL cursor.  For me, I simply 
> put my CHAIN
> inside the READC loop.  How exactly do you get yours to work?
> 
> Joe
> 

Ah, this is the point I've been trying to get across.  You're used to
processing a subfile like this one record at a time.  But if you step back,
you actually have a set of items that need to be processed.  

Obviously, you'd still need to READC the subfile one record at a time.  SQL
can't be used on a display file.  But, it's not a big deal to store the
items you need to process in an array or some other structure in memory to
allow you to process them as a set using SQL.

Let me put together a full fledged program so everybody can see exactly what
we are talking about and that will give us some benchmarks for your IAAI
site.

I'm confident SQL will prove to be better than native when dealing with set
processing.  The interesting question to answer is how big of a set does it
take to make a difference?  The other interesting question is the effect of
added complexity.  If instead of doing 4 chains to the master files (or the
SQL equivalent) we have to do 5 or 6 or 8.

Don't look for the post right away, I'm pretty well book solid today and
tonight.  But I should be able to put something together Wednesday night.

Charles