Hello Jörn,

I need to create an XML document from data in BaseX 11.5 inside basexgui. The data in the database does not use any namespaces. The document I am creating must have a default namespace set. Here is a stripped down example of my XQuery: for $w in /json/workouts/_/header[uuid='123'] return

<gpx xmlns="http://www.topografix.com/GPX/1/1" >   <title>{$w/title/text()}</title> </gpx> Strangely all XPaths inside and outside the gpx-element will not match anything as long as I have the default namespace on the gpx-element defined. It works if I drop the xmlns attribute or I define the namespace explicitly, like: for $w in /json/workouts/_/header[uuid='123'] return <g:gpx xmlns:g="http://www.topografix.com/GPX/1/1" >   <g:title>{$w/title/text()}</g:title> </g:gpx>

I think I made a standalone (no database) example that illustrates your issue:

let $doc := document {   <json>     <workouts>       <_>         <header>           <uuid>123</uuid>           <title>title 1</title>         </header>       </_>       <_>         <header>           <uuid>123</uuid>           <title>title 2</title>         </header>       </_>     </workouts>   </json> } let $gpx1 :=   for $w in $doc/json/workouts/_/header[uuid='123']   let $title := $w/title/text()   return     <gpx xmlns="http://www.topografix.com/GPX/1/1" >       <title>{$w/title/text()}</title>       <titlex>{$w/*:title/text()}</titlex>       <titley>{$title}</titley>     </gpx> let $gpx2 :=   for $w in $doc/json/workouts/_/header[uuid='123'] return     <g:gpx xmlns:g="http://www.topografix.com/GPX/1/1" >       <g:title>{$w/title/text()}</g:title>     </g:gpx> return ( $gpx1 , $gpx2 )

When I run this in the BaseX GUI, I get

<gpx xmlns="http://www.topografix.com/GPX/1/1"><title/><titlex>title 1</titlex><titley>title 1</titley></gpx> <gpx xmlns="http://www.topografix.com/GPX/1/1"><title/><titlex>title 2</titlex><titley>title 2</titley></gpx> <g:gpx xmlns:g="http://www.topografix.com/GPX/1/1%22%3E<g:title>title 1</g:title></g:gpx> <g:gpx xmlns:g="http://www.topografix.com/GPX/1/1%22%3E<g:title>title 2</g:title></g:gpx>

The default namespace on <gpx> becomes the default namespace in the XPath expression. I am not sure if this is correct, and I have not looked this up in the specification.

Maybe someone who is more knowledgeable can tell if this behaviour is correct. For now, I suggest you use the additional $title variable.

Best regards, Nico Verwer

Hi Jörn,

The behavior is compliant with the spec: The default namespace of node tests in path expressions is affected by default namespace declarations (xmlns="") appearing on element constructors.

You can achieve the expected result by using wildcards or the "Q{uri}local" syntax in the path…

$w/*:title/text() $w/Q{}title/text()

…or by moving the path outside the element constructor.

With XQuery 4 (as indicated by Martin), it will be possible to change the default behavior by introducing the query with a declaration that changes the default behavior:

declare fixed default element namespace '';

This syntax will be supported in one of the next versions of BaseX.

Best, Christian

Jörn Willhöft jwi@willhoeft-it.com schrieb am Do., 9. Jan. 2025, 19:23:

Hi all,

I just come across an issue, and I am not sure if I am too stupid to see the mistake, or it is a bug in BaseX.

I need to create an XML document from data in BaseX 11.5 inside basexgui. The data in the database does not use any namespaces. The document I am creating must have a default namespace set. Here is a stripped down example of my XQuery:

for $w in /json/workouts/_/header[uuid='123'] return

<gpx xmlns="http://www.topografix.com/GPX/1/1" > <title>{$w/title/text()}</title> </gpx>

Strangely all XPaths inside and outside the gpx-element will not match anything as long as I have the default namespace on the gpx-element defined. It works if I drop the xmlns attribute or I define the namespace explicitly, like:

for $w in /json/workouts/_/header[uuid='123'] return <g:gpx xmlns:g="http://www.topografix.com/GPX/1/1" > <g:title>{$w/title/text()}</g:title> </g:gpx>

Even though this should be semantically equal to the output of the above, the third party app that I import this to does not recognize it as such.

This is puzzling me mainly because I do not see, why the namespace I define for the *output* xml should have an impact on the queries that are directed to my database. As a workaround I will probably use a regex to remove the namespace, but that's obviously pretty awkward.

Any ideas?

Cheers Jörn