Actually, i am trying to omit the namespaces, not the xml declaration. Sorry for the mistake in my first post, Martin.

So i am looking for something like : @exclude-result-prefixes (as found in XSLT 3.0).

And indeed, in BaseX (9.5.1), it seems to be a different behaviour if the xml source is stored in a let variable or in a db. If the xml source is stored in a variable, the exclusion of prefixes is automatic, as in :

declare namespace marc="http://www.loc.gov/MARC21/slim";

let $xml :=
<marc>
  <marc:record xmlns:marc="http://www.loc.gov/MARC21/slim" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <marc:leader>01321nam a22002772a 4500</marc:leader>
    <c level="item">
      <did>
        <unitid type="division">1808001595</unitid>
      </did>
    </c>
  </marc:record>
</marc>

for $record in $xml/marc:record[1]

return
$record/c 

<c level="item">
  <did>
    <unitid type="division">1808001595</unitid>
  </did>
</c>

Le 25/08/2021 à 15:20, Martin Honnen a écrit :

Am 25.08.2021 um 15:12 schrieb Yann NICOLAS (ABES):

Hi all,

I am looking for the equivalent instruction of XSLT attribute @omit-xml-declaration in XQuery.

In the Query prolog you can declare

declare namespace output = "http://www.w3.org/2010/xslt-xquery-serialization";

declare option output:method 'xml';
declare option output:omit-xml-declaration 'yes';

Thanks Martin.

In the user interface, it is working when the xml source is stored in a let variable, but it's not when the xml source is retrieved from a BaseX db.

declare namespace marc="http://www.loc.gov/MARC21/slim";

declare namespace output = "http://www.w3.org/2010/xslt-xquery-serialization";

declare option output:method 'xml';
declare option output:omit-xml-declaration 'yes';

for $record in db:open('marcxml_full')//marc:record[1]

return
$record/c