Hi Xia, Try this patch: http://treehou.se/~omar/postgresql-8.4.1-array_sel_hack.patch It's a hack, but it works for us. I think you're probably spending most of your query time planning, and this patch helps speed things up 10x over here. Regards, Omar On Sun, Sep 27, 2009 at 5:13 PM, Xia Qingran <qingran.xia@xxxxxxxxx> wrote: > On Sat, Sep 26, 2009 at 10:59 PM, Craig James > <craig_james@xxxxxxxxxxxxxx> wrote: >> >> If your user_id is always in a narrow range like this, or even in any range >> that is a small fraction of the total, then add a range condition, like >> this: >> >> select * from event where user_id <= 500 and user_id >= 0 and user_id in >> (...) >> >> I did this exact same thing in my application and it worked well. >> >> Craig >> > > It is a good idea. But In my application, most of the queries' user_id > are random and difficult to range. > Thanks anyway. > > > > -- > 夏清然 > Xia Qingran > qingran.xia@xxxxxxxxx > Sent from Beijing, 11, China > Charles de Gaulle - "The better I get to know men, the more I find > myself loving dogs." - > http://www.brainyquote.com/quotes/authors/c/charles_de_gaulle.html > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance > -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
