Tamino XQuery User Guide - Software AG Documentation

Text Retrieval
In Tamino, you can use the function tf:stem to retrieve occurrences of all word forms belonging
to the same word stem. Similarly to tf:phonetic, it works only in the scope of one of the search
functions:
let $text :=
Die Bank eröffnete drei neue Filialen im Verlauf der letzten fünf ↩
Jahre.
Ermüdet von dem Spaziergang setzte sich die alte Dame erleichtert auf die
gepflegt wirkende Bank mitten im Stadtpark.
Die aktuelle Bilanz der Bank zeigt einen Anstieg der liquiden Mittel im
Vergleich zum Vorjahresquartal.
for $a in $text//para
let $check :=
for $value in ("Geld", "Bilanz", "Filiale", "monetär", "Aktie")
return tf:containsNearText($a, 10, tf:stem($value), tf:stem("Bank"))
where count($check[. eq true()]) > 0
return $a
This returns all para elements whose text contains at least one word which is related to a specific
reading of the German word "Bank". The resulting document contains the first and the third para
element, but not the second, since it does not contain any of the words defined in the sequence
("Geld", "Bilanz", "Filiale", "monetär", "Aktie") in a distance of less than ten words from
"Bank".
Tamino uses a set of rules to determine whether a word token belongs to some stem. There is a
pre-defined rule set that works reasonably well for German. However, you can create your own
set of rules. See the section Rules for Searches Using Phonetic Values and Stemming below. You
can reach the pre-defined rules set using the following query:
declare namespace ino="http://namespaces.softwareag.com/tamino/response2"
collection("ino:vocabulary")/ino:stemrules
Note: Do not use tf:stem standalone; use it only in the context of one of the following
functions: tf:containsText, tf:containsAdjacentText, tf:containsNearText,
tf:createAdjacentTextReference, tf:createNearTextReference,
tf:createTextReference. The result of calling this function in any other context is unspecified
and might change in a future Tamino version.
XQuery User Guide
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