[SQL] Optimize querry sql
Hi,
I want to optimize my qerry sql (execution time : 2448 ms) :
SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a
,reseller b where b.asp=6 and a.idxreseller=b.reseller and
a.month=date_part('month',now() - interval '1 month') and
a.year=date_part('year',now() - interval '1 month') GROUP BY
b.idxreseller,b.namereseller limit 15;
dns=> \d stat_dns_domaine;
Table «public.stat_dns_domaine»
idxdxreseller | integer | not null
idxdo | integer | not null
idxd | integer | not null
nbrq | integer | default 0
month | integer | default date_part('month'::text, (now() -
'1 mon'::interval))
year| integer | default date_part('year'::text, (now() - '1
mon'::interval))
Index :
«stat_dns_domaine_idx_idxr_idxrevendeur» btree (idxrevendeur)
«stat_dns_domaine_idx_mois_annee_idxrev» btree (mois, annee, idxrevendeur)
\d revendeur limit 20;
Table «public.revendeur»
idxreseller| integer | not null default
nextval(('idxrevendeur_seq'::text)::regclass)
namereseller | text|
asp | integer |
Index :
«reseller_pkey» PRIMARY KEY, btree (idxreseller)
Thank you
STan
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TIP 2: Don't 'kill -9' the postmaster
[SQL] Optimize querry sql
Hi,
I want to optimize my qerry sql (execution time : 2448 ms) :
SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a
,reseller b where b.asp=6 and a.idxreseller=b.reseller and
a.month=date_part('month',now() - interval '1 month') and
a.year=date_part('year',now() - interval '1 month') GROUP BY
b.idxreseller,b.namereseller limit 15;
dns=> \d stat_dns_domaine;
Table «public.stat»
idxdxreseller | integer | not null
idxdo | integer | not null
idxd | integer | not null
nbrq | integer | default 0
month | integer | default date_part('month'::text, (now() -
'1 mon'::interval))
year| integer | default date_part('year'::text, (now() - '1
mon'::interval))
Index :
«stat_dns_domaine_idx_idxr_idxrevendeur» btree (idxrevendeur)
«stat_dns_domaine_idx_mois_annee_idxrev» btree (mois, annee, idxrevendeur)
\d revendeur;
Table «public.reseller»
idxreseller| integer | not null default
nextval(('idxrevendeur_seq'::text)::regclass)
namereseller | text|
asp | integer |
Index :
«reseller_pkey» PRIMARY KEY, btree (idxreseller)
Thank you
Stan
---(end of broadcast)---
TIP 2: Don't 'kill -9' the postmaster
Re: [SQL] Optimize querry sql
am Fri, dem 14.09.2007, um 10:31:39 +0200 mailte Stanislas de Larocque
folgendes:
> Hi,
>
> I want to optimize my qerry sql (execution time : 2448 ms) :
>
> SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a
> ,reseller b where b.asp=6 and a.idxreseller=b.reseller and
> a.month=date_part('month',now() - interval '1 month') and
> a.year=date_part('year',now() - interval '1 month') GROUP BY
> b.idxreseller,b.namereseller limit 15;
Show us the output from EXLAIN ANALYSE .
My guess: you need at least an index in reseller.asp. Why do you have
columns such a.month and a.year? se a regular DATE or TIMESTAMPTZ field
instead and an index on this.
And use CURRENT_DATE instead now().
Andreas
--
Andreas Kretschmer
Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
---(end of broadcast)---
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
Re: [SQL] Optimize querry sql
Hi,
Explain my sql querry :
Limit (cost=1057.15..1057.16 rows=1 width=27)
-> HashAggregate (cost=1057.15..1057.16 rows=1 width=27)
-> Nested Loop (cost=0.00..1057.14 rows=1 width=27)
-> Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8)
Filter: (((month)::double precision =
date_part('month'::text, (now() - '1 mon'::interval))) AND
((year)::double precision = date_part('year'::text, (now() - '1
mon'::interval
-> Index Scan using resaller_pkey on revendeur b
(cost=0.00..14.15 rows=1 width=23)
Index Cond: ("outer".idxresaller = b.idxresaller)
Filter: (asp = 6)
I would optimize "Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8)"
What is your advice ?
Thank you
Stan
2007/9/14, A. Kretschmer <[EMAIL PROTECTED]>:
> am Fri, dem 14.09.2007, um 10:31:39 +0200 mailte Stanislas de Larocque
> folgendes:
> > Hi,
> >
> > I want to optimize my qerry sql (execution time : 2448 ms) :
> >
> > SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a
> > ,reseller b where b.asp=6 and a.idxreseller=b.reseller and
> > a.month=date_part('month',now() - interval '1 month') and
> > a.year=date_part('year',now() - interval '1 month') GROUP BY
> > b.idxreseller,b.namereseller limit 15;
>
> Show us the output from EXLAIN ANALYSE .
>
> My guess: you need at least an index in reseller.asp. Why do you have
> columns such a.month and a.year? se a regular DATE or TIMESTAMPTZ field
> instead and an index on this.
> And use CURRENT_DATE instead now().
>
> Andreas
> --
> Andreas Kretschmer
> Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
> GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
>
> ---(end of broadcast)---
> TIP 9: In versions below 8.0, the planner will ignore your desire to
>choose an index scan if your joining column's datatypes do not
>match
>
---(end of broadcast)---
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
Re: [SQL] Optimize querry sql
am Fri, dem 14.09.2007, um 12:26:00 +0200 mailte Stanislas de Larocque
folgendes:
> Hi,
>
> Explain my sql querry :
>
> Limit (cost=1057.15..1057.16 rows=1 width=27)
>-> HashAggregate (cost=1057.15..1057.16 rows=1 width=27)
> -> Nested Loop (cost=0.00..1057.14 rows=1 width=27)
>-> Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8)
> Filter: (((month)::double precision =
> date_part('month'::text, (now() - '1 mon'::interval))) AND
> ((year)::double precision = date_part('year'::text, (now() - '1
> mon'::interval
>-> Index Scan using resaller_pkey on revendeur b
> (cost=0.00..14.15 rows=1 width=23)
> Index Cond: ("outer".idxresaller = b.idxresaller)
> Filter: (asp = 6)
>
> I would optimize "Seq Scan on stat a (cost=0.00..1042.98 rows=1 width=8)"
>
> What is your advice ?
Create indexes on the columns month and year. But, again, you have an
unpractical table-design.
>
> Thank you
>
> Stan
>
>
> 2007/9/14, A. Kretschmer <[EMAIL PROTECTED]>:
Please no top-posting.
(answer on top and fullquote below)
Andreas
--
Andreas Kretschmer
Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
---(end of broadcast)---
TIP 6: explain analyze is your friend
Re: [SQL] Optimize querry sql
On Fri, Sep 14, 2007 at 12:26:00PM +0200, Stanislas de Larocque wrote: > Explain my sql querry : did you notice, that andreas asked: > > Show us the output from EXLAIN ANALYSE . depesz -- quicksil1er: "postgres is excellent, but like any DB it requires a highly paid DBA. here's my CV!" :) http://www.depesz.com/ - blog dla ciebie (i moje CV) ---(end of broadcast)--- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
[SQL] Optimize querry sql
Hi,
I had errors in my last emails. sorry
I want to optimize my query sql (execution time : 2665 ms) :
SELECT b.idxreseller, sum(a.nbrq), b.namereseller from stat a
,reseller b where b.asp=6 and a.idxreseller=b.reseller and
a.month=date_part('month',now() - interval '1 month') and
a.year=date_part('year',now() - interval '1 month') GROUP BY
b.idxreseller,b.namereseller limit 15;
Explain analyse :
Limit (cost=1057.15..1057.16 rows=1 width=27) (actual
time=2655.083..2655.176 rows=15 loops=1)
-> HashAggregate (cost=1057.15..1057.16 rows=1 width=27) (actual
time=2655.074..2655.132 rows=15 loops=1)
-> Nested Loop (cost=0.00..1057.14 rows=1 width=27) (actual
time=0.646..2464.563 rows=18543 loops=1)
-> Seq Scan on stat a (cost=0.00..1042.98 rows=1
width=8) (actual time=0.273..1239.510 rows=24881 loops=1)
Filter: (((month)::double precision =
date_part('month'::text, (now() - '1 mon'::interval))) AND
((year)::double precision = date_part('year'::text, (now() - '1
mon'::interval
-> Index Scan using reseller_pkey on reseller b
(cost=0.00..14.15 rows=1 width=23) (actual time=0.034..0.038 rows=1
loops=24881)
Index Cond: ("outer".idxrreseller = b.idxreseller)
Filter: (asp = 6)
Total runtime: 2655.713 ms
dns=> \d stat;
Table «public.stat»
idxreseller | integer | not null
idxdo | integer | not null
idxd | integer | not null
nbrq | integer | default 0
month | integer | default date_part('month'::text, (now() -
'1 mon'::interval))
year| integer | default date_part('year'::text, (now() - '1
mon'::interval))
Index :
«stat_dns_domaine_idx_idxr_idxreseller» btree (dxreseller)
«stat_dns_domaine_idx_month_year_idxres» btree (month, year, idxreseller)
\d reseller;
Table «public.reseller»
idxreseller| integer | not null default
nextval(('idxrevendeur_seq'::text)::regclass)
namereseller | text|
asp | integer |
Index :
«reseller_pkey» PRIMARY KEY, btree (idxreseller)
Have you advices ?
Thank you
Stan
---(end of broadcast)---
TIP 2: Don't 'kill -9' the postmaster
Re: [SQL] Optimize querry sql
On 9/14/07, A. Kretschmer <[EMAIL PROTECTED]> wrote: > And use CURRENT_DATE instead now(). Out of curiosity, why the advice to switch from now() to CURRENT_DATE? ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
Re: [SQL] Optimize querry sql
On Fri, Sep 14, 2007 at 03:02:59PM +0200, Stanislas de Larocque wrote:
> I want to optimize my query sql (execution time : 2665 ms) :
SELECT
b.idxreseller,
sum(a.nbrq),
b.namereseller
from
stat a,
reseller b
where
b.asp=6
and a.idxreseller=b.reseller
and a.month=date_part('month',now() - interval '1 month')
and a.year=date_part('year',now() - interval '1 month')
GROUP BY
b.idxreseller,b.namereseller limit 15;
1. cast all date_parts to int4, like in:
a.month = cast( date_part('month',now() - interval '1 month') as int4)
2. why there is a limit without any order by?
3. change it to get namereseller from subselect, not from join.
depesz
--
quicksil1er: "postgres is excellent, but like any DB it requires a
highly paid DBA. here's my CV!" :)
http://www.depesz.com/ - blog dla ciebie (i moje CV)
---(end of broadcast)---
TIP 3: Have you checked our extensive FAQ?
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Re: [SQL] Optimize querry sql
am Fri, dem 14.09.2007, um 8:36:47 -0500 mailte Scott Marlowe folgendes: > On 9/14/07, A. Kretschmer <[EMAIL PROTECTED]> wrote: > > > And use CURRENT_DATE instead now(). > > Out of curiosity, why the advice to switch from now() to CURRENT_DATE? Mhh, don't know... Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
Re: [SQL] Optimize querry sql
On 9/14/07, A. Kretschmer <[EMAIL PROTECTED]> wrote: > am Fri, dem 14.09.2007, um 8:36:47 -0500 mailte Scott Marlowe folgendes: > > On 9/14/07, A. Kretschmer <[EMAIL PROTECTED]> wrote: > > > > > And use CURRENT_DATE instead now(). > > > > Out of curiosity, why the advice to switch from now() to CURRENT_DATE? > > Mhh, don't know... OK, I was just afraid there was some "bad thing" TM that I wasn't aware of with now(), which, btw, I use all the time. whew. ---(end of broadcast)--- TIP 6: explain analyze is your friend
