April 2015 - BaseX-Talk - mailman.uni-konstanz.de

Released: BaseX 8.1.1. Upcoming: Finger trees
by Christian Grün 16 Apr '15

16 Apr '15

Hi all, BaseX 8.1.1 has just been released [1]. It mostly contains minor bug fixes, all of them uncritical. Since recently, our XQuery arrays are based on a Finger tree implementation [2]. This fancy data structure provides much better performance for insert and delete operations. With BaseX 8.2, this data structure is now used for arbitrary sequences. If you want to belong to our early testers, please check out the latest snapshot [3]. We are looking for your feedback! Have fun, Christian [1] http://basex.org/download [2] https://en.wikipedia.org/wiki/Finger_tree [3] http://files.basex.org/releases/latest

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Way to React To Updates Using XQuery?
by Eliot Kimber 16 Apr '15

16 Apr '15

As part of my DITA link management system, I need to create and update various indexes and data structures whenever specific documents are added or updated. I was looking for some sort of trigger or event handler by which I would register an XQuery function and the system would call it on add, update, or delete, but I didn't see anything like that in the docs. Since my updates are, in my case, being driven by git commit hooks I could have the commit hook call a function following updates and pass that function the list of added, updated, and deleted docs. But that would not support the case where documents were loaded by some other route. Is such a mechanism available? Thanks, Eliot ————— Eliot Kimber, Owner Contrext, LLC http://contrext.com

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Xquery update performance on Base 8.1
by Erol Akarsu 15 Apr '15

15 Apr '15

Hello, I am having noticeable performance degradation for updating existing database in this function with Basex 81. I can say this function never finish with 81. But when I replace nodes call with file:append (writing result to a file), I can see it is slowness. But Basex_79 is much faster than Basex81 with regard to this update and finish this function quickly without any issue. I like to upgrade to 81 but because of this issue I could not. Can you help me? declare %updating function local:addCRMSegmentsIntoProducts () { let $allProds := fn:doc("AccumulatedProducts") let $segments := ("Aburcubur","Ãay_Kahve","Ä°Ã§ecek","Karma_Az","Meyve_Sebze","SaÃ§_BakÄ±m","SÃ¼t_Su-Madeaze_TÃ¼ketim","Temizlik") let $productsMap := map:new( for $rec in $allProds//doc let $prodIDField := $rec/field[@name eq "ProductID"] let $pid := $prodIDField/text() return map:entry($pid,$prodIDField)) for tumbling window $prodGroup in fn:doc("CRMSegments")//record start $first next $second when fn:true() end $last next $beyond when $last/PRODUCT_ID ne $beyond/PRODUCT_ID let $pid := $prodGroup[1]/PRODUCT_ID return let $prodEntry := map:get($productsMap,$pid)/.. return if (fn:empty($prodEntry)) then () else let $segData := for $segGroup in $prodGroup let $sid := $segGroup/SON_SEGMENT/text() let $sid := fn:concat("10",fn:index-of($segments,$sid)) group by $sid return let $segAmount := sum($segGroup//AMOUNT/text()) let $segOrderCount := sum($segGroup//ORDER_COUNT) let $segFields := (<field name="SegAmount_{$sid}">{$segAmount}</field>, <field name="SegOrderCount_{$sid}">{$segOrderCount}</field>) return $segFields return insert nodes ($segData) as last into $prodEntry };

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A question about the type system
by Kristian Kankainen 15 Apr '15

15 Apr '15

Hello! I'm not sure whether this is a question relevant to BaseX or more generally to the XQuery community. Since I don't use other XQuery systems and it might be specific to the BaseX parser, I post it here first. Why can't I specify xs:positiveIntegers as literals? Or why can't I treat xs:integers as xs:positiveIntegers? Consider a simple function that takes a xs:positiveInteger as input: <code> xquery version "3.0" encoding "UTF-8"; declare namespace local = "local"; declare function local:positive( $input as xs:positiveInteger ) as xs:positiveInteger { $input }; </code> I get an error XPTY0004 Cannot treat xs:integer as xs:positiveInteger if I run it with a literal input, like this: <code> local:positive(2) </code> I get no error if I specify the type explicitly, like this: <code> local:positive(xs:positiveInteger(2)) </code> This feel very odd, since the type system is hierarchical and xs:positiveInteger is a subcase of xs:integer, I don't really see a problem of this kind of automatic casting of integer literals if they qualify the cast. Can you give any reflection on this? Best regards Kristian Kankainen

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IllegalMonitorStateException at org.basex.core.locks.DBLocking
by Simon Chatelain 14 Apr '15

14 Apr '15

Hello all, I have the following problem. Using: BaseX 8.1.1 beta cf713e2 (20150328.133759) Java 1.8.0_31 Windows 7 The context: I have several sources of data from which I receive XML documents. My application will create a collection for each of these sources and store each received document into the collection corresponding to the source, and then update some kind of metadata about the collection. The metadata of all collections are stored into a common collection. Each source is handled by a different thread. I am using an embedded BaseX, and access to it through LocalSession. Now the problem is that after a certain amount of time (not constant, could be seconds or minutes) there is some exceptions. Either: java.lang.IllegalMonitorStateException at org.basex.core.locks.DBLocking.acquire and org.basex.core.locks.DBLocking.release Or: java.util.ConcurrentModificationException at org.basex.core.users.User.find I put the full stack trace in attachment. I build a test application that mimic what happens in the real application and it seems to exhibit the same problem. The source of this test application is attached My question: Am I doing something wrong, or is there a bug in BaseX? Thanks a lot Simon

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Re: [basex-talk] Mystery Failure on REPLACE but Not ADD
by Eliot Kimber 13 Apr '15

13 Apr '15

It's definitely a function of my local .basex settings. If I revert to the default settings (make the basex install dir .basexhome and remove ~/.basex) then the replace succeeds. Trying to figure out what the setting is that results in the failure. Cheers, E. ————— Eliot Kimber, Owner Contrext, LLC http://contrext.com On 4/12/15, 11:36 AM, "Eliot Kimber" <ekimber(a)contrext.com> wrote: >Using the basex Zip distribution for both 8.0.3 and 8.1, I'm getting a >failure on REPLACE but not ADD for the same XML data. > >This command succeeds: > >basexclient -c "CHECK dfst_dfst-sample-project_master; OPEN >dfst_dfst-sample-project_master; ADD to dfst/metadata.xml ><dfst_metadata/>" > > >But this command fails > >basexclient -c "CHECK dfst_dfst-sample-project_master; OPEN >dfst_dfst-sample-project_master; REPLACE dfst/metadata.xml ><dfst_metadata/>" > >"..." (Line 1): Premature end of file. > > >This definitely worked in the past, so something must have changed on my >system. > >Obviously, the error message is not very helpful in this case. > >Any idea what the problem might be or how I would diagnose this failure? > >Thanks, > >E. > >————— >Eliot Kimber, Owner >Contrext, LLC >http://contrext.com > > > >

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xpointer
by Jerome Chauveau 13 Apr '15

13 Apr '15

Hi, Are xpointer implemented in BaseX 8? I tried to add an xpointer attribute in an xinclude element but it failed. [a] <xi:include href="plop.xml"/> [b] <xi:include href="plop.xml" xpointer="myId"/> [a] works fine but [b] fails (Fallback is called). Thanks for help, Jérôme.

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Documentation on Module Imports Missing a Detail
by Eliot Kimber 12 Apr '15

12 Apr '15

I was trying to have a RESTXQ module import a library module stored in the configured REPO directory. I copied my module into that directory and verified that it was listed: Name Version Type Path ----------------------------------------------------- basex-utils - Internal basex-utils.xqm dita-utils - Internal dita-utils.xqm linkmgmt-utils - Internal linkmgmt-utils.xqm relpath-utils - Internal relpath-utils.xqm 4 package(s). Where I want to import the basex-utils module. The docs say: <lq> Repository modules are stored in a directory named BaseXRepo or repo, which resides in your home directory <http://docs.basex.org/wiki/Configuration#Home_Directory>. XQuery modules can be manually copied to the repository directory or installed and deleted via commands <http://docs.basex.org/wiki/Repository#Commands>. If a modules is placed in the repository, there is no need to specify a location. </lq> However, this import failed to find the module: import module namespace bxutil="http://dita-for-small-teams.org/xquery/modules/basex-utils"; But, after I did an explicit REPO INSTALL on the module, BaseX put it in a directory that mirrors the namespace URL structure. At that point the import succeeded. Thus, it appears that the module needs to be installed or otherwise stored in a directory that mirrors the namespace declaration--it is not sufficient to simply copy the module into the repo directory. I think this assumption that the namespace URI will be a URL is not valid. If I create a module that uses a URN for the namespace URI, I get this failure on REPO INSTALL: [bxerr:BXRE0002] URI is invalid or has no path component: 'urn:names:xquerymodule:testurn'. In the case of URNs, the token separator is ":", so you could treat each token as a directory name. Cheers, Eliot

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Mystery Failure on REPLACE but Not ADD
by Eliot Kimber 12 Apr '15

12 Apr '15

Using the basex Zip distribution for both 8.0.3 and 8.1, I'm getting a failure on REPLACE but not ADD for the same XML data. This command succeeds: basexclient -c "CHECK dfst_dfst-sample-project_master; OPEN dfst_dfst-sample-project_master; ADD to dfst/metadata.xml <dfst_metadata/>" But this command fails basexclient -c "CHECK dfst_dfst-sample-project_master; OPEN dfst_dfst-sample-project_master; REPLACE dfst/metadata.xml <dfst_metadata/>" "..." (Line 1): Premature end of file. This definitely worked in the past, so something must have changed on my system. Obviously, the error message is not very helpful in this case. Any idea what the problem might be or how I would diagnose this failure? Thanks, E. ————— Eliot Kimber, Owner Contrext, LLC http://contrext.com

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HTTP Server Not Serving Any RESTXQ Results
by Eliot Kimber 12 Apr '15

12 Apr '15

I'm trying to set up some basic Web services using the basexhttp server. I'm on OS X. If I understand the docs, after running the basexhttp command, I should get the sample HTML start page returned by page:start() function defined in the restxq.xqm file when I go to http://localhost:8984 However I'm not getting that page, I'm getting a 404 response from the Jetty server: HTTP ERROR 404Problem accessing /. Reason: No function found that matches the request. Powered by Jetty:// I verified that restxq.xqm is a loaded module: > repo list Name Version Type Path ------------------------------------- - Internal .DS_Store restxq - Internal restxq.xqm 2 package(s). > I'm sure this worked when I first started playing with BaseX and installed it initially. I tried both 8.0.3 (the first version I used) and 8.1 with no difference. I must have done something to the configuration to cause this problem but I don't see any obvious mistake on my part: I haven't knowingly changed the web.xml or jetty.xml files and web.xml seems to clearly enable handling of root URLs by the RESTXQ handler: <servlet> <servlet-name>RESTXQ</servlet-name> <servlet-class>org.basex.http.restxq.RestXqServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>RESTXQ</servlet-name> <url-pattern>/*</url-pattern> </servlet-mapping> The WebDAV service does work: I can retrieve files from specific databases using the WeDAV url. Any suggestions on where my configuration might be bad? Thanks, Eliot ————— Eliot Kimber, Owner Contrext, LLC http://contrext.com

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