thanks, I actually do use eq not = ...
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Micah Dubinko Sent: Tuesday, November 10, 2009 6:41 PM To: General Mark Logic Developer Discussion Subject: Re: [MarkLogic Dev General] Optimize exact match searches onattributes David, I'm guessing the optimizer already does this, but just in case, try using the atomic comparison operator eq instead of =. (The value in $code will never be a sequence, right?) > $root/tree/item[ @code eq $code ] Even though it goes against conventional wisdom, also try $root//item [ ... ] You can use xdmp:elapsed-time() to get decent resolution timing data to experiment with what works the fastest. -m On Nov 10, 2009, at 3:15 PM, Lee, David wrote: > Suppose I have an XML document with about 50,000 of these small > elements > <item name="Peritoneum" parent="A01.047.025" > code="A01.047.025.600"/> > > And an Xquery that does a LOT of this kind of search > > let $item = $root/tree/item[ @code = $code ] > or > let $item = $root/tree/item[ @parent = $code ] > > > These are exact string matches, no fancy terming or wildcards or > anything. > > Any suggestions on the basic area to look for optimizing this kind > of access ? Either using xquery or a setting on the server ? > Thanks for any suggestions. So far I've only been able to find > things tailored for full text searching (1 letter, 2 letter, word > searches etc). > I would think direct attribute=value searches could be tagged for > efficient indexing. Maybe they are already ? > But its starting to slow down when I do about 20 of these in an > xquery. > > One thought I had was to preprocess the data into more of a tree > structure instead of the flat structure it is now ... > <item > > <item> > <item> > </item> > </item> > > then I can use ancestor axis to search up the tree instead of a flat > search ... But if these were already indexed it "should" be a near > instant access as a flat structure (???) > > > > ---------------------------------------- > David A. Lee > Senior Principal Software Engineer > Epocrates, Inc. > [email protected] > 812-482-5224 > > > _______________________________________________ > General mailing list > [email protected] > http://xqzone.com/mailman/listinfo/general _______________________________________________ General mailing list [email protected] http://xqzone.com/mailman/listinfo/general _______________________________________________ General mailing list [email protected] http://xqzone.com/mailman/listinfo/general
