is not shown on output:

<programlisting>
SELECT 'a:1A fat:2B,4C cat:5D'::tsvector;
          tsvector
----------------------------
 'a':1A 'cat':5 'fat':2B,4C
</programlisting>

     Weights are typically used to reflect document structure, for example
     by marking title words differently from body words.  Text search
     ranking functions can assign different priorities to the different
     weight markers.
    </para>

    <para>
     It is important to understand that the
     <type>tsvector</type> type itself does not perform any word
     normalization; it assumes the words it is given are normalized
     appropriately for the application.  For example,

<programlisting>
SELECT 'The Fat Rats'::tsvector;
      tsvector
--------------------
 'Fat' 'Rats' 'The'
</programlisting>

     For most English-text-searching applications the above words would
     be considered non-normalized, but <type>tsvector</type> doesn't care.
     Raw document text should usually be passed through
     <function>to_tsvector</function> to normalize the words appropriately
     for searching:

<programlisting>
SELECT to_tsvector('english', 'The Fat Rats');
   to_tsvector
-----------------
 'fat':2 'rat':3
</programlisting>

     Again, see <xref linkend="textsearch"/> for more detail.
    </para>

   </sect2>

   <sect2 id="datatype-tsquery">
    <title><type>tsquery</type></title>

    <indexterm>
     <primary>tsquery (data type)</primary>
    </indexterm>

    <para>
     A <type>tsquery</type> value stores lexemes that are to be
     searched for, and can combine them using the Boolean operators
     <literal>&amp;</literal> (AND), <literal>|</literal> (OR), and
     <literal>!</literal> (NOT), as well as the phrase search operator
     <literal>&lt;-&gt;</literal> (FOLLOWED BY).  There is also a variant
     <literal>&lt;<replaceable>N</replaceable>&gt;</literal> of the FOLLOWED BY
     operator, where <replaceable>N</replaceable> is an integer constant that
     specifies the distance between the two lexemes being searched
     for.  <literal>&lt;-&gt;</literal> is equivalent to <literal>&lt;1&gt;</literal>.
    </para>

    <para>
     Parentheses can be used to enforce grouping of these operators.
     In the absence of parentheses, <literal>!</literal> (NOT) binds most tightly,
     <literal>&lt;-&gt;</literal> (FOLLOWED BY) next most tightly, then
     <literal>&amp;</literal> (AND), with <literal>|</literal> (OR) binding
     the least tightly.
    </para>

    <para>
     Here are some examples:

<programlisting>
SELECT 'fat &amp; rat'::tsquery;
    tsquery
---------------
 'fat' &amp; 'rat'

SELECT 'fat &amp; (rat | cat)'::tsquery;
          tsquery
---------------------------
 'fat' &amp; ( 'rat' | 'cat' )

SELECT 'fat &amp; rat &amp; ! cat'::tsquery;
        tsquery
------------------------
 'fat' &amp; 'rat' &amp; !'cat'
</programlisting>
    </para>

    <para>
     Optionally, lexemes in a <type>tsquery</type> can be labeled with
     one or more weight letters, which restricts them to match only
     <type>tsvector</type> lexemes with one of those weights:

<programlisting>
SELECT 'fat:ab &amp; cat'::tsquery;
    tsquery
------------------
 'fat':AB &amp; 'cat'
</programlisting>
    </para>

    <para>
     Also, lexemes in a <type>tsquery</type> can be labeled with <literal>*</literal>
     to specify prefix matching:
<programlisting>
SELECT 'super:*'::tsquery;
  tsquery
-----------
 'super':*
</programlisting>
     This query will match any word in a <type>tsvector</type> that begins
     with <quote>super</quote>.
    </para>

    <para>
     Quoting rules for lexemes are the same as described previously for
     lexemes in <type>tsvector</type>; and, as with <type>tsvector</type>,
     any required normalization of words must be done before converting
     to the <type>tsquery</type> type.  The <function>to_tsquery</function>
     function is convenient for performing such normalization:

<programlisting>
SELECT to_tsquery('Fat:ab