× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.



Sorry... I should have mentioned that I've already been through some of these explanations.

It's returning a count of 20-40 (that's how many rows meet the criteria)... The Select is using
OPTIMIZE FOR 250 ROWS (as suggested by the IBM DB group)

The SQL statements are executing within a CGI application... so I can only really control the source (view) and the indexes.

-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxxxxxxxx] On Behalf Of Charles Wilt
Sent: Wednesday, June 17, 2020 1:12 PM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: Hash Table Probe

Greg,

When running a statement from STRSQL or Run SQL Scripts, the default is
optimize=*FIRSTIO

Which means, give me back the first set of rows as quickly as possible,
even if it means getting the full set will take longer.

Try setting optimize=*ALLIO

That should get you closer, however you're likely to still see a difference
since the Db (and Run SQL Scripts in particular) pages back the results set
if you're returning more than a few hundred rows..

Charles


On Wed, Jun 17, 2020 at 9:09 AM Greg Wilburn <
gwilburn@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

I have and SQL COUNT statement running over a complex SQL View... The
SELECT statement of the same rows takes 1-2 seconds. The COUNT(*) takes
6-8 seconds.

When I ran this through RUN SQL SCRIPTS using run & explain, I see:
Hash Probe <- Temporary Hash Table <- Table Probe

The Table Probe is 90% of the time used. I'm just not sure how to
eliminate or reduce the amount of CPU time this takes.
I already have quite a few indexes over the DB2 table... I can see that in
the "List of Indexes Optimized"

Anyone point me in the right direction?
--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: https://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx
Before posting, please take a moment to review the archives
at https://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
questions.

Help support midrange.com by shopping at amazon.com with our affiliate
link: https://amazon.midrange.com


As an Amazon Associate we earn from qualifying purchases.

This thread ...

Follow-Ups:
Replies:

Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.