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From Nirmal Fernando <nirmal070...@gmail.com>
Subject Re: JIRA Issues that would nice to have a Graphical Query Plan Attached
Date Tue, 13 Jul 2010 16:59:12 GMT
Hi Eranda,

Please see my comments inline.

> Did you do it to prepared statement?

I did it for this query:
SELECT a.USER_ID, a.USER_NAME, b.account_id FROM Users a JOIN
Messaged_Users b ON a.USER_ID=b.USER_ID AND b.account_id=(?)

I suppose you need to know the query plan followed by the optimizer,
for that query.

> Also need a little explanation to understand the doc.

It's still in very basic HTML stage, sorry if it's not that clear.
It displays the plan followed by the optimizer as a tree.
In this case query has executed like:

PROJECTION
     |
     |
HASHJOIN
     |
 _  |_____________
|                           |
TABLESCAN         HASHSCAN

Under each node selected portion of details are shown
if they're not null.

If you want to know the meanings of entries in tables
you can refer to sysxplain tables
(http://db.apache.org/derby/docs/dev/ref/rref_xplain_tables.html).

Thanks.

> Thanks
> Eranda
>
> On Tue, Jul 13, 2010 at 9:39 PM, Nirmal Fernando <nirmal070125@gmail.com>
> wrote:
>>
>> Hi Eranda,
>>
>> I've attached a PDF to the JIRA issue.
>>
>> Thanks for the request!
>>
>> On Tue, Jul 13, 2010 at 2:09 PM, Eranda Sooriyabandara
>> <erandajira@gmail.com> wrote:
>> >
>> > Hi Nirmal,
>> > Can you do it for the following issue
>> > https://issues.apache.org/jira/browse/DERBY-3892
>> > Thanks
>> > Eranda
>> > On Tue, Jul 13, 2010 at 12:47 PM, Nirmal Fernando
>> > <nirmal070125@gmail.com> wrote:
>> >>
>> >> Hi All,
>> >>
>> >> These days we're testing the basic HTMLs generated using
>> >> PlanExporter tool. So, I would really happy to attach Graphical Query
>> >> Plans
>> >> for JIRA issues which may possibly helpful to understand where's
>> >> the problem.
>> >>
>> >> If you know any issues that generates wrong results please reply to
>> >> this thread,
>> >> with the link to the JIRA. It would be nice if you have sql commands to
>> >> setup
>> >> the environment needed to that issue.
>> >>
>> >> Please note that issues with exceptions/assert failure can't import to
>> >> a Graphical Query Plan,
>> >> since as for those queries, there's no statistics captured by Xplain
>> >> tables.
>> >>
>> >> Thanks.
>> >>
>> >> --
>> >> Best Regards,
>> >> Nirmal
>> >>
>> >> C.S.Nirmal J. Fernando
>> >> Department of Computer Science & Engineering,
>> >> Faculty of Engineering,
>> >> University of Moratuwa,
>> >> Sri Lanka.
>> >>
>> >
>>
>>
>>
>> --
>> Best Regards,
>> Nirmal
>>
>> C.S.Nirmal J. Fernando
>> Department of Computer Science & Engineering,
>> Faculty of Engineering,
>> University of Moratuwa,
>> Sri Lanka.
>
>



-- 
Best Regards,
Nirmal

C.S.Nirmal J. Fernando
Department of Computer Science & Engineering,
Faculty of Engineering,
University of Moratuwa,
Sri Lanka.

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