RE: Populating fields based on field name in a file

The reason for that statement is due to the design model given.  Dynamic
SQL requires additional overhead that static SQL does not.  In order to
use SQL with the design model given there is additional I/O to retrieve
all field defaults via RPG(or SQL) to build the SQL statement, then the
execution of the SQL statement that was built.

I use embedded SQL quite often.  Generally the performance hit comes in
how you have to formulate the SQL for dynamic statements.  Also I
recommend not using EXECUTE IMMEDIATE as opposed to PREPARE & EXECUTE
for production processes (one-offs go for it...)

The optimizer (though a great thing..) can only do so much.  Database (&
process) design have more impact on how SQL (or native I/O) performs
than any other thing I can think of.  

Just my 2 cp... 


Thanks,
Tommy Holden


-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Buck
Sent: Tuesday, October 25, 2005 11:21 AM
To: rpg400-l@xxxxxxxxxxxx
Subject: Re: Populating fields based on field name in a file

 > using dynamic SQL  which for this
 > purpose (IMO would perform very
 > poorly...)

I strongly suggest that the original poster try the dynamic SQL before
throwing it out as a poor performer.  It may run pitifully slow too, but
you just don't know until you try.

What performs badly on my machine with my dataset may scream on yours,
and vice versa.  SQL is very unlike traditional RPG I/O because of the
optimiser, which makes sweeping statements about SQL performance
problematic at best.
   --buck
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