Bureaucrats, editor, reviewer, Administrators
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Please note that scoring propagation was removed with {{Mark|Version 9.5}}. The following expressions will now yield {{Code|0}}: <syntaxhighlight lang="xquery">let $string := 'a b'return ft:score($string contains text 'a' and $string contains text 'b'), for $n score $s in db:open('factbook')//religions[text() contains text 'orthodox']order by $s descendingreturn $s || ': ' || $n</syntaxhighlight> Scoring is still supported within full-text expressions, by {{Function|Full-Text|ft:search}}, and by simple predicate tests that can be rewritten to {{Function|Full-Text|ft:search}}:
The reason for removing the scoring propagation was that the storage of scoring values required additional memory, even if scoring is not required.
BaseX supports One or more thesaurus files can be specified in a full-text queries using thesauri, but it does not provide a default thesaurusexpression. This is why queries such asThe following query returns {{Code|false}}:
will return If a thesaurus is employed… <syntaxhighlight lang="xml"><thesaurus xmlns="http://www.w3.org/2007/xqftts/thesaurus"> <entry> <term>computers</term> <synonym> <term>hardware</term> <relationship>NT</relationship> <code/synonym>false </codeentry>. However, if the </thesaurus is specified, then the ></syntaxhighlight> …the result will be {{Code|true}}: <codesyntaxhighlight lang="xquery">true'hardware' contains text 'computers' using thesaurus at 'thesaurus.xml'</codesyntaxhighlight> Thesaurus files must comply with the [https://dev.w3.org/2007/xpath-full-text-10-test-suite/TestSuiteStagingArea/TestSources/thesaurus.xsd XSD Schema] of the XQFT Test Suite (but the namespace can be omitted). Apart from the relationship defined in [https://www.iso.org/standard/7776.html ISO 2788] (NT: narrower team, RT: related term, etc.), custom relationships can be used. The type of relationship and the level depth can be specified as well:
The format of the thesaurus files must More details can be the same as the format of the thesauri provided by found in the [https://devwww.w3.org/2007TR/xpath-full-text-10-test-suite XQuery and XPath Full Text 1.0 Test Suite]. It is an XML with structure defined by an [https://dev.w3.org/2007/xpath-full-text-10-test-suite/TestSuiteStagingArea/TestSources/thesaurus.xsd XSD Schema#ftthesaurusoption specification].
→Fuzzy Querying
</syntaxhighlight>
<syntaxhighlight lang="xquery">
return $s || ': ' || $n
</syntaxhighlight>
==Thesaurus==
<syntaxhighlight lang="xquery">
'computershardware' contains text 'hardwarecomputers'
using thesaurus default
</syntaxhighlight>
<syntaxhighlight lang="xquery">
(: BT: find broader terms; NT means narrower term :)
'computers' contains text 'hardware'
using thesaurus at 'XQFTTS_1_0_4/TestSources/usability2x.xml'relationship 'BT' from 1 to 10 levels
</syntaxhighlight>
==Fuzzy Querying==
</syntaxhighlight>
Fuzzy search is based on the Levenshtein distance. The maximum number of allowed errors is calculated by dividing the token length of a specified query term by 4, preserving a minimum of 1 errors. The query above yields two results as there is no error between the query term “house” and the text node “house”, and one error between “house” and “hous”.
A user-defined value can be adjusted globally via the {{Option|LSERROR}} option or, since {{Version|9.6}}, via an additional argument:
<syntaxhighlight lang="xquery">
