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 at > http://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.
