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42th chunk of `doc/src/sgml/textsearch.sgml`
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 <replaceable
   class="parameter">config</replaceable>,
   or <varname>default_text_search_config</varname> if that argument is
   omitted.
  </para>

  <para>
   <function>ts_debug</function> returns one row for each token identified in the text
   by the parser.  The columns returned are

    <itemizedlist  spacing="compact" mark="bullet">
     <listitem>
      <para>
       <replaceable>alias</replaceable> <type>text</type> &mdash; short name of the token type
      </para>
     </listitem>
     <listitem>
      <para>
       <replaceable>description</replaceable> <type>text</type> &mdash; description of the
       token type
      </para>
     </listitem>
     <listitem>
      <para>
       <replaceable>token</replaceable> <type>text</type> &mdash; text of the token
      </para>
     </listitem>
     <listitem>
      <para>
       <replaceable>dictionaries</replaceable> <type>regdictionary[]</type> &mdash; the
       dictionaries selected by the configuration for this token type
      </para>
     </listitem>
     <listitem>
      <para>
       <replaceable>dictionary</replaceable> <type>regdictionary</type> &mdash; the dictionary
       that recognized the token, or <literal>NULL</literal> if none did
      </para>
     </listitem>
     <listitem>
      <para>
       <replaceable>lexemes</replaceable> <type>text[]</type> &mdash; the lexeme(s) produced
       by the dictionary that recognized the token, or <literal>NULL</literal> if
       none did; an empty array (<literal>{}</literal>) means it was recognized as a
       stop word
      </para>
     </listitem>
    </itemizedlist>
  </para>

  <para>
   Here is a simple example:

<screen>
SELECT * FROM ts_debug('english', 'a fat  cat sat on a mat - it ate a fat rats');
   alias   |   description   | token |  dictionaries  |  dictionary  | lexemes
-----------+-----------------+-------+----------------+--------------+---------
 asciiword | Word, all ASCII | a     | {english_stem} | english_stem | {}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | fat   | {english_stem} | english_stem | {fat}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | cat   | {english_stem} | english_stem | {cat}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | sat   | {english_stem} | english_stem | {sat}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | on    | {english_stem} | english_stem | {}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | a     | {english_stem} | english_stem | {}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | mat   | {english_stem} | english_stem | {mat}
 blank     | Space symbols   |       | {}             |              |
 blank     | Space symbols   | -     | {}             |              |
 asciiword | Word, all ASCII | it    | {english_stem} | english_stem | {}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | ate   | {english_stem} | english_stem | {ate}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | a     | {english_stem} | english_stem | {}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | fat   | {english_stem} | english_stem | {fat}
 blank     | Space symbols   |       | {}             |              |
 asciiword | Word, all ASCII | rats  | {english_stem} | english_stem | {rat}
</screen>
  </para>

  <para>
   For a more extensive demonstration, we
   first create a <literal>public.english</literal> configuration and
   Ispell dictionary for the English language:
  </para>

<programlisting>
CREATE TEXT SEARCH CONFIGURATION public.english ( COPY = pg_catalog.english );

CREATE TEXT SEARCH DICTIONARY
Title: Detailed Explanation of `ts_debug` Output and Examples
Summary
This section elaborates on the output of the `ts_debug` function, detailing each column returned: alias, description, token, dictionaries, dictionary, and lexemes. It explains the meaning of each column, including how an empty array in the 'lexemes' column indicates a stop word. The section then provides a simple example of using `ts_debug` with the 'english' configuration and shows the resulting output. Finally, it introduces the creation of a `public.english` configuration and Ispell dictionary for further demonstration.