Someone on the list gave me following tip: ********************************************************* for $i in index-scan("chemicalcontent_id", "", "GE")/@id return string($i) - as a result, you will get the keyset of an index, maybe with duplicate keys (if they are presented in index), which can be removed with distinct-values function.
Here, the blank key to compare with ( "" ) assumed to be less than any other key in index. ********************************************************* But I tried that and it still is not responsive. I think Sedna is not using the index only but still doing a full collection scan. Can someone shed some light on this? I was also looking a bit into the documentation for how to run an explain plan. But to my surprise I don't see anything back of index usage. It's something I would typically expect from an explain plan. http://www.sedna.org/progguide/ProgGuidesu10.html#x16-640002.7.3 To give an example, I have following index and xquery module ******************************************************************* create index "package_id" on fn:collection("packages/released")/Package by @identifier as xs:string ******************************************************************* module namespace packages = "http://www.nxp.com/packages"; declare function packages:getPackage($id as xs:string) as element(Package)? { index-scan('package_id', $id, 'EQ') }; ******************************************************************* Now I tried to explain a method invocation that uses a index: ******************************************************************* explain import module namespace packages = "http://www.nxp.com/packages"; packages:getPackage("SOT669") ******************************************************************* It shows me following explanation, but no evidence of an index being used. ******************************************************************* <prolog xmlns="http://www.modis.ispras.ru/sedna"/> <query xmlns="http://www.modis.ispras.ru/sedna"> <operation name="PPQueryRoot"> <operation name="PPFunCall" id="0" function-name="packages:getPackage" position="3:1"> <operation name="PPConst" type="xs:string" value="SOT669" position="3:21"/> </operation> </operation> </query> ******************************************************************* So any tips on debugging my performance problem are very welcome !! Thx in advance, Robby -----Original Message----- From: Robby Pelssers [mailto:robby.pelss...@nxp.com] Sent: Thursday, January 10, 2013 12:09 PM To: sedna-discussion@lists.sourceforge.net Subject: [Sedna-discussion] poor performance for large collection Hi all, I have a single collection of 24468 documents. <count>{count(collection("chemicalContent/released")/TypeName)}</count> == 24468 When I just try to run below statement it takes very long to execute. The documents themselves are not even that big varying between 2kb and 12kb. for $i in collection("chemicalContent/released") return document-uri($i) I also have a index on that collection: create index "chemicalcontent_id" on fn:collection("chemicalContent/released")/TypeName by @id as xs:string Is it normal for that statement to execute that long (> 1 minute) ? Is there a way to perhaps speed up fetching a list of all @id's for that particular collection? Thx in advance, Robby ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnmore_122712 _______________________________________________ Sedna-discussion mailing list Sedna-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sedna-discussion ------------------------------------------------------------------------------ Master HTML5, CSS3, ASP.NET, MVC, AJAX, Knockout.js, Web API and much more. Get web development skills now with LearnDevNow - 350+ hours of step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only -- learn more at: http://p.sf.net/sfu/learnmore_122812 _______________________________________________ Sedna-discussion mailing list Sedna-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sedna-discussion