| From: | Guillaume Lelarge <guillaume(at)lelarge(dot)info> |
|---|---|
| To: | boris pezzatti <boris(dot)pezzatti(at)wsl(dot)ch> |
| Cc: | pgadmin-support(at)postgresql(dot)org |
| Subject: | Re: very slow when writing query to file |
| Date: | 2011-11-03 11:20:48 |
| Message-ID: | 1320319248.2130.29.camel@localhost.localdomain |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgadmin-support |
On Thu, 2011-11-03 at 12:02 +0100, Guillaume Lelarge wrote:
> On Thu, 2011-11-03 at 11:22 +0100, boris pezzatti wrote:
> > I tested after column types, and the colum that appears to create the
> > very slow behaviour is of type boolean. Retrieving only 1 column for
> > 3000 records delays at ca. 1 minute.
> >
> > Do you know any possible reason?
> >
>
> That's good to know. I tried with a boolean column, which gave me 7
> seconds for 10000 rows. Which doesn't seem much, but it's actually 7
> times more than without the boolean column.
>
> It seems we keep executing the same SQL command, 10000 times (actually
> as much as your number of rows). And that is weird.
>
> I'll look into this.
>
OK, found it. We introduced some time ago a cache for type lookup. It
seems the boolean type doesn't make it to the cache. The patch is
commited. It should be available with the release of 1.14.1.
--
Guillaume
http://blog.guillaume.lelarge.info
http://www.dalibo.com
| From | Date | Subject | |
|---|---|---|---|
| Next Message | boris pezzatti | 2011-11-03 15:35:16 | Re: very slow when writing query to file |
| Previous Message | Guillaume Lelarge | 2011-11-03 11:02:22 | Re: very slow when writing query to file |