August 2022 - BaseX-Talk - mailman.uni-konstanz.de

BaseX 9.6: The Summer Edition
by Christian Grün 28 Nov '24

28 Nov '24

Dear all, We provide you with a new and fresh version of BaseX, our open source XML framework, database system and XQuery 3.1 processor: https://basex.org/ Apart from our main focus (query rewritings and optimizations), we have added the following enhancements: XQUERY: MODULES, FEATURES - Archive Module, archive:write: stream large archives to file - SQL Module: support for more SQL types - Full-Text Module, ft:thesaurus: perform Thesaurus queries - Fulltext, fuzzy search: specify Levenshtein limit - UNROLLLIMIT option: control limit for unrolling loops XQUERY: JAVA BINDINGS - Java objects of unknown type are wrapped into function items - results of constructor calls are returned as function items - the standard package "java.lang." has become optional - array arguments can be specified with the middle dot notation - conversion can be controlled with the WRAPJAVA option - better support for XQuery arrays and maps WEB APPLICATIONS - RESTXQ: Server-Timing HTTP headers are attached to the response For a more comprehensive list of added and updated features, look into our documentation (docs.basex.org) and check out the GitHub issues (github.com/BaseXdb/basex/issues) Have fun, Your BaseX Team

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recursively used variables
by Rob Stapper 12 Aug '24

12 Aug '24

Hi, The code[1] below and send as attachment generates a error message: “Static variable depends on itself: $Q{http://www.w3.org/2005/xquery-local-functions}test”. I use these variables to refer to my private functions in my modules so I can easyly refer to them in a inheritance situation. It’s not a big problem for me but I was wondering if the error-triggering is justified or that it should work. [1]=========================================== declare variable $local:test := local:test#1 ; declare %private function local:test( $i) { if ( $i > 0) then $local:test( $i - 1) } ; $local:test( 10) =========================================== Kind regards, Rob Stapper Sent from Mail for Windows 10 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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xslt:transform-report result
by Andy Bunce 11 Mar '24

11 Mar '24

Hi, Using BaseX 9.7.1 and saxon9he-9.9.1.jar The documentation suggests the ?result from xslt:transform-report should be *a* document-node where possible [1] This seems not quite to be the case when there are processing instructions or comments at the top level. In these cases a sequence of document-nodes is returned. /Andy [1] https://docs.basex.org/wiki/XSLT_Module#xslt:transform-report let $xslt:=<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="3.0"> <xsl:mode on-no-match="shallow-copy"/> </xsl:stylesheet> let $xml:=document{ <?something type="compact"?>, <foo/>} return xslt:transform-report($xml,$xslt) Returns map { "messages": (), "result": (<?something type="compact"?>, <foo/>) }

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Problem with validate:xsd-report
by Hans-Juergen Rennau 01 Sep '22

01 Sep '22

Dear BaseX people, I encounter a problem with validate:xsd-report(), more particular with using a schema importing the well-known xml.xsd. The imported attribute declaration (xml:base) is not found. I am pretty sure that it is my fault, but I just can't find my error - could you take a look? (1) Document: doc.xml <book xml:base="/a/b/c" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="schema.xsd"> <author>xyz</author></book> (2) Schema: schema.xsd <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified"> <xs:import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="xml.xsd"/> <xs:element name="book"> <xs:complexType> <xs:sequence> <xs:element name="author" type="xs:string"/> </xs:sequence> <xs:attribute ref="xml:base"/> </xs:complexType> </xs:element></xs:schema> (In the same folder, a downloaded copy of xml.xsd is stored - for a snippet, see PS) (3) Query: validate.xq let $doc := 'doc.xml'let $xsd := 'schema.xsd'return validate:xsd-report($doc, $xsd) (4) Result: basex validate.xq=><report> <status>invalid</status> <message level="Fatal" line="9" column="43" url="file:/C:/projects/d2type/jats/test-validation/schema.xsd">src-resolve: Cannot resolve the name 'xml:base' to a(n) 'attribute declaration' component. </message></report> I do not understand why the import seems to be ignored. Validating with oXygen works fine, but I suppose that oXygen ignores the @schemaLocation. If you see the reason, please let me know. Cheers,Hans-Jürgen PS: Snippet from xml.xsd, stored in the same folder: <?xml version='1.0'?><!DOCTYPE xs:schema PUBLIC "-//W3C//DTD XMLSCHEMA 200102//EN" "XMLSchema.dtd" ><xs:schema targetNamespace="http://www.w3.org/XML/1998/namespace" xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="en"> ... <xs:attribute name="base" type="xs:anyURI"> <xs:annotation> <xs:documentation>See http://www.w3.org/TR/xmlbase/ for information about this attribute.</xs:documentation> </xs:annotation> </xs:attribute> ...</xs:schema>

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Exception handling in XQuery-Java-Binding
by Andreas Hengsbach | nexoma 29 Aug '22

29 Aug '22

Hi, I am currently experimenting with java code loaded as a basex module. There I throw custom exceptions, which I want to catch and handle in XQuery. Unfortunately, the information about the thrown Java exception seems to get lost. What options do I have to throw my own error messages from my java module that do not immediately become "XPTY0004"? Many thanks and best regards Andreas

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Re: [basex-talk] an Earley parser in XQuery?
by C. M. Sperberg-McQueen 25 Aug '22

25 Aug '22

On 23 August 2022, Graydon Saunders wrote: > On Mon, Aug 22, 2022 at 07:42:39PM +0200, Martin Honnen scripsit: > > On 22.08.2022 19:07, Graydon Saunders wrote: > > > I'm trying to test if some extracted sentences validate as productions > > > of a particular context-free grammar expressed in a BNF dialect. > > > > > > Is there an available implementation of a parser in XQuery that can do > > > this? > > > > > In the context of Invisible XML https://invisiblexml.org/ I have heard > > that term "Earley" parser a lot but I am not familiar enough with the > > various implementations to tell whether all are "Earley" parsers, > > https://github.com/cmsmcq/Aparecium is an XQuery implementation of > > Invisible XML. For what it's worth: Of the ixml processors I'm familiar with, all use (or can use) Earley parsers to parse the input string against the input grammar; Norm Walsh's Coffeepot and its related libraries also make a GLL parser available, which is sometimes faster and sometimes slower. About half use the same parser to parse the input grammar against the spec grammar; about half have a hand-written parser for the ixml spec grammar. > And thus interesting, but alas too slow for the application I have. If you are willing and able to send me a copy of your grammar and some sample data, I would be grateful; it might help me improve the situation with respect to Aparecium's performance. Both Norm Walsh's processor and John Lumley's processor are currently a lot faster than Aparecium, though I don't know a simple way to call them directly from XQuery. Another alternative, if you have speed issues and just one grammar you are interested in, is to use Gunther Rademacher's REx parser generator to compile the grammar you are interested in into a parser written in XQuery (other target languages are also available). https://bottlecaps.de/rex/ -- C. M. Sperberg-McQueen Black Mesa Technologies LLC http://blackmesatech.com

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an Earley parser in XQuery?
by Graydon Saunders 23 Aug '22

23 Aug '22

Hello -- I'm trying to test if some extracted sentences validate as productions of a particular context-free grammar expressed in a BNF dialect. Is there an available implementation of a parser in XQuery that can do this? Thanks! Graydon

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Very niche question about BaseX 9.5.1 and java bindings
by Andy Bunce 22 Aug '22

22 Aug '22

Hi, I am trying to write a Java property file using v9.5.1 and no new Java code. The code below runs in 9.7.3. Although it only uses 9.5 features in 9.5.1 it produces the error message props:store·java.io.Writer·String cannot be called with (Writer, String). but https://docs.oracle.com/javase/8/docs/api/java/util/Properties.html#store-j… I assume this is a 9.5.1 java binding bug? Any workaround suggestions or details of what the problem is? /Andy ----------------------------------------------- (:~ Using Basex 9.5.1 and assuming a file "test.properties" in folder containing this module:) import module namespace props = "java:java.util.Properties"; declare variable $source:= file:resolve-path("test.properties",file:base-dir()) !(prof:void(props:load·java.io.Reader(Q{java:java.io.FileReader}new(.))),.) ; props:store·java.io.Writer·String( Q{java:java.io.FileWriter}new($source), "The saucer has landed")

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Basex 10.1, cannot execute query for a particular file name
by ykhabins＠bellsouth.net 19 Aug '22

19 Aug '22

Hello, Congrats on the release of BaseX 10.1 I decided to try XQuery 4.0 functionality right away. So, I typed a new query without saving it on the file system as follows: xquery version "4.0"; (1 to 5) -> {. + .} Executed it, and it is worked. I saved it as a file name: [xquery version 4.0] without square brackets. Extension is 0 And I cannot execute it anymore. Why is that? Just when I saved it as [xquery version 4.xq], I was able to execute it again. Just a peculiarity. Regards, Yitzhak Khabinsky

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Memory footprint for a certain query is much higher usisng BaseX10 compared to 9
by Alexander Witzigmann 16 Aug '22

16 Aug '22

Hi, BaseX 10 has a different behavior in memory footprint for the following situation. To avoid passing around data you can create db using the following create (i did this with BaseX 9) declare variable $input := <root><sheet name="SAP">{for $idx in (1 to 10000) return <row>{for $e in $enames return element {$e} { attribute {"content"} {$idx}}}</row>}</sheet></root>; db:create("test-db",$input,"test.xml") Then using the following query on the created db: declare variable $input := db:open("test-db"); <root>{ for $s in $input//sheet[./@name => contains("SAP")] return <sheet>{$s/@*}{ for $r in $s//row let $no := $r/Objektkurztext/@content return <row>{$r/@*}{($r/*,<partno>{$no}</partno>)}</row> }</sheet> }</root> Using BaseX 9 the used memory for the query is round about 2 GB which is ok. Using BaseX 10 Out-of-Memory exception happens in my case used memory is > 12 GB Any thoughts what the reason is - any additional information required? Alex

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