<entry><type>real</type></entry>

<entry>

Same as <function>word_similarity(text, text)</function>, but forces

extent boundaries to match word boundaries.

extent boundaries to match word boundaries. Since we don't have

cross-word trigrams, this function actually returns greatest similarity

between first string and any continuous extent of words of the second

string.

</entry>

</row>

<row>

This function returns a value that can be approximately understood as the

greatest similarity between the first string and any substring of the second

string. However, this function does not add padding to the boundaries of

the extent. Thus,a whole word match gets a higher score than a match with

a part ofthe word.

the extent. Thus,the number of additional characters present in the

second string is not considered, except forthemismatchedword boundry.

</para>

<para>

At the same time, <function>strict_word_similarity(text, text)</function>

has to select an extent that matches word boundaries. In the example above,

selects extent of words in the second string. In the example above,

<function>strict_word_similarity(text, text)</function> would select the

extent<literal>{" w"," wo","wor","ord","rds","ds "}</literal>,which

corresponds to the whole word <literal>'words'</literal>.

extentof single word <literal>'words'</literal>,whose set of trigrams is

<literal>{" w"," wo","wor","ord","rds","ds "}</literal>

<programlisting>

# SELECT strict_word_similarity('word', 'two words'), similarity('word', 'words');

<para>

Thus, the <function>strict_word_similarity(text, text)</function> function

is useful for findingsimilar subsets of whole words, while

is useful for findingthe similarity to whole words, while

<function>word_similarity(text, text)</function> is more suitable for

searching similar parts of words.

finding the similarity for parts of words.

</para>

<table id="pgtrgm-op-table">