RE: DB2 AS/400 client connector

Thanks for your useful input Vern.
BB

-----Original Message-----
From: Vern Hamberg [mailto:vhamberg@xxxxxxxxxxxxxxxxxxxxxxxxx]
Sent: Tuesday, August 26, 2003 5:40 PM
To: Midrange Systems Technical Discussion
Subject: RE: DB2 AS/400 client connector


IMO, at least 2 things contribute to good ODBC performance:

1. Appropriate index support for the SQL statements generated. We have 
products that address this issue specifically. Ops Nav also has some help 
in this area, I believe.

2. Minimize the amount of data that crosses the network, and keep as much 
processing on the 400 as possible - this is common to Crystal, as well, 
which suggests transferring as much processing as possible to the server, 
whatever the type.

In this light, try to control what the SQL looks like. I don't know Cognos, 
I use Crystal, and you are able to write native SQL that will run on the 
400, instead of summary processing that may run on the PC.

In addition, stored procedures can give much better performance, esp. since 
they can limit the amount of data coming down to the PC.

You can find more info 
<http://www-1.ibm.com/servers/eserver/iseries/perfmgmt/resource.htm> There 
are various performance books there, including 
<http://publib.boulder.ibm.com/iseries/v5r2/ic2924/books/as4ppcp8.pdf>, 
which, in Chapter 10, has stuff on client/server and remote access. It's 
fairly general, with some suggestions.

You can also find an ODBC guide on the iseries access site - one still in 
use is old but good, ODBC User's Guide or some such - great stuff on 
performance.

HTH

Vern

>
>Management thinks there may be performance issues with ODBC and that one
>method of connecting may be better than the other performance-wise.  Do you
>have any performance issues?


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