RE: More, Re: Questions about RPG service program as an SQL UDF

I would suggest trying it in iNav if you can. I had a similar event happen with some bad logic in an SQL view that would run the first time in JasperReports over JDBC fine, but then subsequent times would use tons of CPU appearing to try to optimize (based on looking at the job call stack). For the longest time I thought it was a JasperReports problem, because I couldn't reliably duplicate it in iNav. Then I realized it never happened on the first call, but only on the second requests even in iNav.

Also I believe iNav and BIRT will both be using a JDBC connection so you should be able to get similar results.


-Tom Stieger
IT Manager
California Fine Wire



-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of James H. H. Lampert
Sent: Thursday, February 28, 2013 8:39 AM
To: RPG programming on the IBM i (AS/400 and iSeries)
Subject: Re: More, Re: Questions about RPG service program as an SQL UDF

On 2/27/13 5:57 PM, Vernon Hamberg wrote:

I suspect that, just as it is when using a function in a WHERE clause,
that this often causes a full table scan, esp. when it is something
like

function(column) = value

The bizarre and unexplained issue is that the censorship function adds only a modest 11 seconds to the response time when I benchmark it by counting the rows in the view (which would have to call the censorship function for every single record), yet it adds at least 15 minutes to the response time when a BIRT report is run. Yet when I added diagnostic code, to log the initialization of the censorship function and each record passed to it, running the BIRT report logged exactly one trip through the entire file, and four additional calls to specific records.

And (based on my recollections of a class I took in Rochester back in
2005) I was under the impression that Visual Explain required one to run the query through iNav, or something connected to iNav. How would that help me with BIRT?

--
JHHL