Tamino XQuery User Guide - Software AG Documentation

Text Retrieval
for $a in input()/patient
where tf:containsText($a/occupation, "diver")
return { $a/name }
Now Tamino returns Mr. Atkins in the diver list, since the tokenizer identifies "Diver" as a word,
delimited on the left by a space character. After applying lower case as standard tokenizer rule
the token "diver" is found and the function tf:containsText returns true. Please note that this
function looks for word tokens, so using tf:containsText($a/occupation, "dive") would yield
false, since "dive" is not a token that can be found in any of the occupation nodes. Similarly, a
query using tf:containsText($a/occupation, "professional diver") returns true, since the
two word tokens are found in that order in the occupation node. However,
tf:containsText($a/occupation, "diver professional") returns false: Although both tokens
are found, they are not in the specified order.
Context Operations
With context operations you can search for expressions that consist of one or more words which
do not necessarily follow after one another. For example, you can search for variants of the expression
"text retrieval" such as "retrieval of text" or in "text storage and retrieval". In Tamino, there
are functions that let you specify the following context operations (here, "#" stands for one token):
■ Maximum word distance
"text # # retrieval" matches "text retrieval" and "text storage and retrieval"
■ Word order
If word order is not significant, "text retrieval" matches "text retrieval" and "retrieval of text"
The functions tf:containsAdjacentText and tf:containsNearText both expect a maximum
word distance as second argument. Consider the following query:
let $text := text{"One, Two, Three, Four, Can I have a little more?"}
return tf:containsAdjacentText($text, 9, "one", "more")
This graphics shows you the search string, its tokens and how the query matches the search string:
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