pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Greg Williamson <gwilliamson39@yahoo.com>
To: tuanhoanganh <hatuan05@gmail.com>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: PostgreSQL 9.0.1 on Windows performance tunning help please
Date: Fri, 5 Aug 2011 20:09:43 -0700 (PDT)
Message-ID: <1312600183.31294.YahooMailNeo@web46113.mail.sp1.yahoo.com> (raw)
In-Reply-To: <CAJg-yaN9GY2xZ=kCbK0icD6bqzM1nWmDrab7hduQDXLKL=RGxQ@mail.gmail.com>
References: <CAJg-yaMyR03J43RLMToB27YdtK7w-vguot2fYKz+0sFHVRsjwA@mail.gmail.com>
	<4E3BE02B020000250003FB8A@gw.wicourts.gov>
	<CAJg-yaN9GY2xZ=kCbK0icD6bqzM1nWmDrab7hduQDXLKL=RGxQ@mail.gmail.com>

Tuan --

> 
> Thanks for your help.
> I create index on channel_id and data_id like your comment. 
...
<...>
> 
> explain analyze select d.data_id, d.table_name, d.event_type, d.row_data, d.pk_data, d.old_data, d.create_time, d.trigger_hist_id, d.channel_id, d.transaction_id, > d.source_node_id, d.external_data, '' from sym_data d inner join sym_data_gap g on g.status='GP' and d.data_id between g.start_id and g.end_id where
> d.channel_id='sale_transaction' order by d.data_id asc;
>
> Nested Loop  (cost=0.00..1512979014.35 rows=26268463088 width=1401) (actual time=25741.704..7650979.311 rows=2764140 loops=1)
>   ->  Index Scan using idx_d_channel_id3 on sym_data d  (cost=0.00..1781979.40 rows=3117384 width=1401) (actual time=83.718..55126.002 rows=3124631 loops=1)
>   ->  Index Scan using sym_data_gap_pkey on sym_data_gap g  (cost=0.00..358.37 rows=8426 width=8) (actual time=2.428..2.429 rows=1 loops=3124631)
>        Index Cond: ((d.data_id >= g.start_id) AND (d.data_id <= g.end_id))
>         Filter: (g.status = 'GP'::bpchar)
> Total runtime: 7651803.073 ms
> 
> But query performance don't change.
> Please help me.

Did you run an analyze on the table after building the new indexes ? The row estimates seem to be off wildly,
although that may be a symptom of something else and not related, it is worth ruling out the easily tried.

HTH,

Greg Williamson




view thread (9+ messages)  latest in thread

Message-ID: <1312600183.31294.YahooMailNeo@web46113.mail.sp1.yahoo.com>
Permalink:  ../1312600183.31294.YahooMailNeo@web46113.mail.sp1.yahoo.com/
Also on:    postgresql.org/message-id/1312600183.31294.YahooMailNeo@web46113.mail.sp1.yahoo.com

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-performance@postgresql.org
  Cc: gwilliamson39@yahoo.com, hatuan05@gmail.com, Kevin.Grittner@wicourts.gov
  Subject: Re: PostgreSQL 9.0.1 on Windows performance tunning help please
  In-Reply-To: <1312600183.31294.YahooMailNeo@web46113.mail.sp1.yahoo.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox