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Please note that scoring propagation was removed with Scoring is supported within full-text expressions, by {{MarkFunction|Full-Text|Version 9.5ft:search}}. The following expressions will now yield , and by simple predicate tests that can be rewritten to {{CodeFunction|Full-Text|0ft:search}}:
for $n score $s in db:open('factbook')//religions[text() contains text 'orthodox']
return $s,
<syntaxhighlight lang="xquery">
let for $string n score $s in db:= open('a bfactbook'return ft:score)//text($string )[. contains text 'aorthodox' ftand ]order by $s descendingreturn $s || 'b: ')|| $n
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… <codesyntaxhighlight lang="xml">false<thesaurus xmlns="http:/code>/www.w3. However, if the org/2007/xqftts/thesaurus is specified, then the result will be "> <entry> <term>computers</term> <synonym> <term>hardware</term> <relationship>NT</relationship> </synonym> </entry><code/thesaurus>true</codesyntaxhighlight> …the result will be {{Code|true}}:
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 search is also supported by the full-<syntaxhighlight lang="xquery">//a[text index.() contains text 'house' using fuzzy 3 errors]</syntaxhighlight>
* Removed: Scoring propagation.
; Version 9.2:
→Fuzzy Querying
</syntaxhighlight>
<syntaxhighlight lang="xquery">
let $string := 'a b'
return ft:score($string contains text 'a' and $string contains text ftand 'b')</syntaxhighlight> Scoring is still supported within full-text expressions and by {{Function|Full-Text|ft:search}}:,
for $n score $s in ft:search('factbook', 'orthodox')
order by $s descendingreturn $s|| ': ' || $n,
</syntaxhighlight>
==Thesaurus==
<syntaxhighlight lang="xquery">
'computershardware' contains text 'hardwarecomputers'
using thesaurus default
</syntaxhighlight>
<syntaxhighlight lang="xquery">
'hardware' contains text 'computers'
using thesaurus at 'thesaurus.xml'
</syntaxhighlight>
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:
<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. A static error distance can be set by adjusting the {{Option|LSERROR}} option (default: <code>SET LSERROR 0</code>). 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 via an additional argument:
=Mixed Content=
=Changelog=
; Version 9.6
* Updated: [[#Fuzzy_Querying|Fuzzy Querying]]: Specify Levenshtein error
; Version 9.5:
* Removed: Scoring propagation.
; Version 9.2:
* Added: Arabic stemmer.
; Version 8.0:
* Updated: [[#Scoring|Scores]] will be propagated by the {{Code|and}} and {{Code|or}} expressions and in predicates.
; Version 7.7:
* Added: [[#Collations|Collations]] support.
; Version 7.3:
* Removed: Trie index, which was specialized on wildcard queries. The fuzzy index now supports both wildcard and fuzzy queries.
* Removed: TF/IDF scoring was discarded in favor of the internal scoring model.
