Обсуждение: Postgres respond after toomany times to a query view

<p><font face="Arial" size="2">Hi, I am  developing a program using postgres and linux like operating system. My
problemis this:</font><br /><font face="Arial" size="2">I have a quite complicated view with roughly 10000 record. When
Iexecute a simple query like this </font><br />        <font face="Arial" size="2">"select * from myview"</font><br
/><fontface="Arial" size="2">postgres respond after 50 - 55 minutes roughly. I hope that someone can help me with some
suggestionabout reason of this behavior and some solution to reduce time ti have results. Thank you for your attentions
andI hope to receive some feedback as soon as possible</font> 

-----Original Message-----
From: Claudia D'amato [mailto:claudia.damato@allaxia.com]
Sent: Tuesday, December 16, 2003 2:32 AM
To: pgsql-hackers@postgresql.org
Subject: [HACKERS] Postgres respond after toomany times to a query view

Hi, I am  developing a program using postgres and linux like operating system. My problem is this:
I have a quite complicated view with roughly 10000 record. When I execute a simple query like this
        "select * from myview"
postgres respond after 50 - 55 minutes roughly. I hope that someone can help me with some suggestion about reason of this behavior and some solution to reduce time ti have results. Thank you for your attentions and I hope to receive some feedback as soon as possible

On Tuesday 16 December 2003 10:32, Claudia D'amato wrote:
> I have a quite complicated view with roughly 10000 record. When I execute a
> simple query like this
>     "select * from myview"
> postgres respond after 50 - 55 minutes roughly. I hope that someone can
> help me with some suggestion about reason of this behavior and some
> solution to reduce time ti have results. Thank you for your attentions and
> I hope to receive some feedback as soon as possible

Hi Claudio - you don't want the hackers list, you probably want the 
performance list. You will want to do the following first:

1. VACUUM ANALYZE the tables used by the view.
2. Provide the output of EXPLAIN ANALYSE SELECT * FROM myview;
3. Provide the definitions of the tables used, and how many rows are in each 
table.


I'll see you on the performance list, and we'll see if we can't help you this 
afternoon.

--  Richard Huxton Archonet Ltd

Dann Corbit kirjutas T, 16.12.2003 kell 12:40:
> I suspect if you do "explain" against the SQL of the view, the answer
> will be apparent.
>  
> Donning my "Karnak the magnificent hat {borrowed from Johnny Carson}":
> You are missing an index.
>  
> For the best help, post the SQL of your view, and also the Schema
> definition for the tables involved.

Also, the best place for asking about performance is the
pgsql-performance list :)

------------
Hannu