I've profile it

1. Session.query:     2.8 seconds
2. Session.execute: 2.6 seconds
3. sqlite.execute:      2.6 seconds

4. If u run it directly via Sqlite Gui client (SQLite Expert) then i
get: 50 ms

Maybe its using some kind of cache.


On 25 feb., 00:42, Michael Bayer <[email protected]> wrote:
> On Feb 24, 2010, at 6:15 PM, dusans wrote:
>
>
>
>
>
> > Hi. I got this simple query thats running very slow:
> > Im working on sqlalchemy 0.6 0.6beta1, sqlite3, python 2.5, windows xp
>
> > 1. I've addet News.[title] to make it run faster, but its still very
> > very slow
>
> > == Code (10 seconds) == :
> > Session.query(News.title, KernelResults).\
> >                            select_from(join(News, KernelResults,
> > News.news_id == KernelResults.news_id_2)).\
> >                            filter(KernelResults.news_id_1 ==
> > c.news_id).\
> >                            filter(KernelResults.kernel_id == 0).\
> >                            order_by(desc(KernelResults.similarity))[:
> > 8]
>
> > == The SQL (50 miliseconds) ==:
> > SELECT
> > news.title AS news_title,
> > kernel_results.id_row AS kernel_results_id_row,
> > kernel_results.news_id_1 AS
> > kernel_results_news_id_1,
> > kernel_results.news_id_2 AS kernel_results_news_id_2,
> > kernel_results.similarity AS kernel_results_similarity,
> > kernel_results .kernel_id AS kernel_results_kernel_id
> > FROM news
> >    JOIN kernel_results
> >            ON news.news_id = kernel_results.news_id_2
> > WHERE kernel_results.news_id_1 = 66
> > AND kernel_results.kernel_id = 0
> > ORDER BY kernel_results.similarity DESC
> > LIMIT 8 OFFSET 0
>
> > Could someone please help me? im still fresh with sqlalchemy :)
>
> there's nothing apparent which would cause such slowness unless you have a 
> high degree of network overhead when your SQLAlchemy application runs, or for 
> example one or more of the columns returned represents an enormous text or 
> binary field, perhaps.   For 8 rows and a 50ms query the total time spent 
> should be in the ballpark of well under 100 ms.
>
>
>
>
>
> > --
> > You received this message because you are subscribed to the Google Groups 
> > "sqlalchemy" group.
> > To post to this group, send email to [email protected].
> > To unsubscribe from this group, send email to 
> > [email protected].
> > For more options, visit this group 
> > athttp://groups.google.com/group/sqlalchemy?hl=en.

-- 
You received this message because you are subscribed to the Google Groups 
"sqlalchemy" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/sqlalchemy?hl=en.

Reply via email to