Re: Hash Table Probe

[Charles Wilt <charles.wilt@xxxxxxxxx>]

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