Re: Horribly slow query/ sequential scan - Mailing list pgsql-performance

Thanks for the suggestion ... I will try it when I've had some sleep and the server is quiet again ... the IN seems to
haveimproved markedly since the 7.4 release, as advertised, so I will be interested in trying this. 

GSW

-----Original Message-----
From:    Nörder-Tuitje, Marcus [mailto:noerder-tuitje@technology.de]
Sent:    Tue 1/9/2007 4:50 AM
To:    db@zigo.dhs.org; Gregory S. Williamson
Cc:    pgsql-performance@postgresql.org
Subject:    AW: [PERFORM] Horribly slow query/ sequential scan

Forget abount "IN". Its horribly slow.

try :

select w.appid,
       w.rate,
       w.is_subscribed,
       sum(w.hits) AS Hits,
       sum(w.sius) AS IUs,
       sum(w.total_amnt) AS Total,
       sum(w.hits) * w.rate AS ByHits,
       sum(w.sius) * w.rate AS BYIUS
  from bill_rpt_work w
 where (select b.report_id from billing_reports b where b.report_s_date = '2006-09-30' and w.report_id = b.report_id)
   and w.client_id IN ('227400001','2274000010')
group by 1,2,3
order by 1,2,3;



should by faster;

assuming : index on report_id in b; index on report_id, client_id in w

to enforce useage of indexes on grouping (depends on result size), consider extending w with cols 1,2,3.


regards,
marcus

-----Ursprüngliche Nachricht-----
Von: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org]Im Auftrag von
db@zigo.dhs.org
Gesendet: Dienstag, 9. Januar 2007 13:36
An: Gregory S. Williamson
Cc: pgsql-performance@postgresql.org
Betreff: Re: [PERFORM] Horribly slow query/ sequential scan


I don't think I understand the idea behind this query. Do you really need
billing_reports twice?

> The query:
> explain analyze select
> w.appid,w.rate,w.is_subscribed,sum(w.hits) AS Hits ,sum(w.sius) AS IUs,
> sum(w.total_amnt) AS Total,sum(w.hits) * w.rate AS ByHits,
> sum(w.sius) * w.rate AS BYIUS
> from bill_rpt_work w, billing_reports b
> where w.report_id in
> (select b.report_id from billing_reports where b.report_s_date =
> '2006-09-30')
> and (w.client_id = '227400001' or w.client_id = '2274000010')
> group by 1,2,3
> order by 1,2,3;

Maybe this is the query you want instead?

select w.appid,
       w.rate,
       w.is_subscribed,
       sum(w.hits) AS Hits,
       sum(w.sius) AS IUs,
       sum(w.total_amnt) AS Total,
       sum(w.hits) * w.rate AS ByHits,
       sum(w.sius) * w.rate AS BYIUS
  from bill_rpt_work w
 where w.report_id in
       (select b.report_id from billing_reports b where b.report_s_date =
'2006-09-30')
   and (w.client_id = '227400001' or w.client_id = '2274000010')
group by 1,2,3
order by 1,2,3;

/Dennis


---------------------------(end of broadcast)---------------------------
TIP 7: You can help support the PostgreSQL project by donating at

                http://www.postgresql.org/about/donate




-------------------------------------------------------
Click link below if it is SPAM gsw@globexplorer.com

"https://mailscanner.globexplorer.com/dspam/dspam.cgi?signatureID=45a38ea050372117817174&user=gsw@globexplorer.com&retrain=spam&template=history&history_page=1"
!DSPAM:45a38ea050372117817174!
-------------------------------------------------------