Re: psql performance - Mailing list pgsql-general

It doesn't matter what the query is.  The problem happens before it even
runs the query.  Just try pasting select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa' union select
'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa';

... and see how long it takes just to get to the point where it executes
the query.

Incidentally when I did that I only got back one row.  What's up with that?

Dann Corbit wrote:
> What is the query?
> What is the schema for the tables in the query?
> What is the cardinality of the tables?
>
> What does the planner say, when you do this:
> explain <query>
> explain analyze <query>
>
> http://www.faqs.org/docs/ppbook/r26943.htm
>
> -----Original Message-----
> From: pgsql-general-owner@postgresql.org
> [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Joseph
> Shraibman
> Sent: Thursday, April 14, 2005 6:19 PM
> To: pgsql-general
> Subject: [GENERAL] psql performance
>
> How come when I paste a large query into psql it starts off fast but
> then slows to a crawl eating up cpu just echoing the query back to me?
> I'm using psql 7.4.7
>
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