Re: Query Optimization - Mailing list pgsql-performance

From A. Kretschmer
Subject Re: Query Optimization
Date
Msg-id 20100408140329.GD29013@a-kretschmer.de
Whole thread Raw
In response to Query Optimization  (Kaloyan Iliev Iliev <kaloyan@digsys.bg>)
List pgsql-performance
In response to Kaloyan Iliev Iliev :
> Hi,
> Can anyone suggest why this query so slow.


>                        ->  Index Scan using
> ms_commands_history_ms_device_id_idx on ms_commands_history ch
> (cost=0.00..4.33 rows=1 width=8) (actual time=0.163..25254.004 rows=9807
> loops=1)

Estimated rows: 1, actual rows: 9807, that's a BIG difference and,
maybe, your problem.

Btw.: your explain is hard to read (line-wrapping). It's better to
attach the explain as an own file...


Andreas
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Andreas Kretschmer
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