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From: Andy <frum@ar-sd.net>
To: Thomas F. O'Connell <tfo@sitening.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Strange join...maybe some improvements???
Date: Thu, 13 Oct 2005 21:28:57 +0300
Message-ID: <00a401c5d023$fac45210$0b00a8c0@forge> (raw)
References: <001d01c5cf34$2df7f100$0b00a8c0@forge>
	<282DBF35-C713-4359-97D5-E8308A5DB226@sitening.com>

Indexes are on all join fields. In the shown example on all fields I have indexes. 

Yes I vacuum the database regulary. 

Andy.

----- Original Message ----- 
  From: Thomas F. O'Connell 
  To: Andy 
  Cc: pgsql-sql@postgresql.org 
  Sent: Thursday, October 13, 2005 7:58 PM
  Subject: Re: [SQL] Strange join...maybe some improvements???


  What indexes do you have on these tables?


  And have you ANALYZEd all three recently?


  --
  Thomas F. O'Connell
  Co-Founder, Information Architect
  Sitening, LLC


  Open Source Solutions. Optimized Web Development.


  http://www.sitening.com/
  110 30th Avenue North, Suite 6
  Nashville, TN 37203-6320
  615-469-5150
  615-469-5151 (fax)



  On Oct 12, 2005, at 8:52 AM, Andy wrote:


    I have 3 tables:
    CREATE TABLE orders
    (
      id int4 SERIAL,
      id_ag int4,
      id_modell int4 ->> this is linked to the modell.id
    ) 

    CREATE TABLE modell
    (
      id int4 SERIAL,
      id_hersteller int4)

    CREATE TABLE contactpartner
    (
      id int4 SERIAL,
      id_ag int4, ->> this is linked to order.id_ag or modell.id_hersteller
    id_user int4
     ).

    I get a list of id_ag from the contactpartner which belongs to a user(AG_LIST). Then I have to selectselect/count all the data's from the order table that have the order.id_ag in the AG LIST or which have the modell.id_hersteller in the AG_LIST. 

    I have this query:

    SELECT count(o.id) FROM orders o
    INNER JOIN modell m ON m.id=o.id_modell
    WHERE o.id_ag IN (SELECT id_ag FROM contactpartner cp WHERE id_user=15) OR m.id_hersteller IN (SELECT id_ag FROM contactpartner cp WHERE id_user=15)

    Aggregate  (cost=7828.60..7828.60 rows=1 width=4) (actual time=1145.150..1145.151 rows=1 loops=1)
      ->  Hash Join  (cost=1689.64..7706.32 rows=48913 width=4) (actual time=153.059..1136.457 rows=9395 loops=1)
            Hash Cond: ("outer".id_modell = "inner".id)
            Join Filter: ((hashed subplan) OR (hashed subplan))
            ->  Seq Scan on orders o  (cost=0.00..3129.17 rows=65217 width=12) (actual time=0.031..94.444 rows=65217 loops=1)
            ->  Hash  (cost=1218.07..1218.07 rows=66607 width=8) (actual time=151.211..151.211 rows=0 loops=1)
                  ->  Seq Scan on modell m  (cost=0.00..1218.07 rows=66607 width=8) (actual time=0.044..87.154 rows=66607 loops=1)
            SubPlan
              ->  Index Scan using contactpartner_id_user_idx on contactpartner cp  (cost=0.00..6.02 rows=2 width=4) (actual time=0.010..0.018 rows=4 loops=1)
                    Index Cond: (id_user = 15)
              ->  Index Scan using contactpartner_id_user_idx on contactpartner cp  (cost=0.00..6.02 rows=2 width=4) (actual time=0.092..0.116 rows=4 loops=1)
                    Index Cond: (id_user = 15)
    Total runtime: 1145.689 ms


    I tried also this one:

    SELECT count(o.id) FROM orders o
    INNER JOIN modell m ON m.id=o.id_modell
    INNER JOIN contactpartner cp ON cp.id_user=15 AND (o.id_ag=cp.id_ag OR cp.id_ag=m.id_hersteller)

    Aggregate  (cost=11658.63..11658.63 rows=1 width=4) (actual time=1691.570..1691.570 rows=1 loops=1)
      ->  Nested Loop  (cost=7752.40..11657.27 rows=542 width=4) (actual time=213.945..1683.515 rows=9416 loops=1)
            Join Filter: (("inner".id_ag = "outer".id_ag) OR ("outer".id_ag = "inner".id_hersteller))
            ->  Index Scan using contactpartner_id_user_idx on contactpartner cp  (cost=0.00..6.02 rows=2 width=4) (actual time=0.108..0.188 rows=4 loops=1)
                  Index Cond: (id_user = 15)
            ->  Materialize  (cost=7752.40..8723.57 rows=65217 width=12) (actual time=37.586..352.620 rows=65217 loops=4)
                  ->  Hash Join  (cost=1677.59..7368.18 rows=65217 width=12) (actual time=150.220..1153.872 rows=65217 loops=1)
                        Hash Cond: ("outer".id_modell = "inner".id)
                        ->  Seq Scan on orders o  (cost=0.00..3129.17 rows=65217 width=12) (actual time=0.034..95.133 rows=65217 loops=1)
                        ->  Hash  (cost=1218.07..1218.07 rows=66607 width=8) (actual time=149.961..149.961 rows=0 loops=1)
                              ->  Seq Scan on modell m  (cost=0.00..1218.07 rows=66607 width=8) (actual time=0.032..86.378 rows=66607 loops=1)
    Total runtime: 1696.253 ms


    >>>>>>>> but this brings me some double information(the same o.id) in the situation in which the o.id_ag and m.id_hersteller are different, but still both in the AG_LIST. 


    Is there any way to speed up this query???

    Regards, 
    Andy.

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  To: pgsql-sql@postgresql.org
  Cc: frum@ar-sd.net, tfo@sitening.com
  Subject: Re: Strange join...maybe some improvements???
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