role="func_table_entry"><para role="func_signature">
        <function>crosstab</function> ( <parameter>source_sql</parameter> <type>text</type>, <parameter>category_sql</parameter> <type>text</type> )
        <returnvalue>setof record</returnvalue>
       </para>
       <para>
        Produces a <quote>pivot table</quote>
        with the value columns specified by a second query.
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <function>crosstab</function> ( <parameter>sql</parameter> <type>text</type>, <parameter>N</parameter> <type>integer</type> )
        <returnvalue>setof record</returnvalue>
       </para>
       <para>
        Obsolete version of <function>crosstab(text)</function>.
        The parameter <parameter>N</parameter> is now ignored, since the
        number of value columns is always determined by the calling query.
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm><primary>connectby</primary></indexterm>
        <function>connectby</function> ( <parameter>relname</parameter> <type>text</type>, <parameter>keyid_fld</parameter> <type>text</type>, <parameter>parent_keyid_fld</parameter> <type>text</type>
        <optional>, <parameter>orderby_fld</parameter> <type>text</type> </optional>, <parameter>start_with</parameter> <type>text</type>, <parameter>max_depth</parameter> <type>integer</type>
        <optional>, <parameter>branch_delim</parameter> <type>text</type> </optional> )
        <returnvalue>setof record</returnvalue>
       </para>
       <para>
        Produces a representation of a hierarchical tree structure.
        </para></entry>
      </row>
     </tbody>
    </tgroup>
  </table>

  <sect3 id="tablefunc-functions-normal-rand">
   <title><function>normal_rand</function></title>

   <indexterm>
    <primary>normal_rand</primary>
   </indexterm>

<synopsis>
normal_rand(int numvals, float8 mean, float8 stddev) returns setof float8
</synopsis>

    <para>
     <function>normal_rand</function> produces a set of normally distributed random
     values (Gaussian distribution).
    </para>

    <para>
     <parameter>numvals</parameter> is the number of values to be returned
     from the function. <parameter>mean</parameter> is the mean of the normal
     distribution of values and <parameter>stddev</parameter> is the standard
     deviation of the normal distribution of values.
    </para>

    <para>
     For example, this call requests 1000 values with a mean of 5 and a
     standard deviation of 3:
    </para>

<screen>
test=# SELECT * FROM normal_rand(1000, 5, 3);
     normal_rand
----------------------
     1.56556322244898
     9.10040991424657
     5.36957140345079
   -0.369151492880995
    0.283600703686639
       .
       .
       .
     4.82992125404908
     9.71308014517282
     2.49639286969028
(1000 rows)
</screen>
  </sect3>

  <sect3 id="tablefunc-functions-crosstab-text">
   <title><function>crosstab(text)</function></title>

   <indexterm>
    <primary>crosstab</primary>
   </indexterm>

<synopsis>
crosstab(text sql)
crosstab(text sql, int N)
</synopsis>

   <para>
    The <function>crosstab</function> function is used to produce <quote>pivot</quote>
    displays, wherein data is listed across the page rather than down.
    For example, we might have data like
<programlisting>
row1    val11
row1    val12
row1    val13
...
row2    val21
row2    val22
row2    val23
...
</programlisting>
    which we wish to display like
<programlisting>
row1    val11   val12   val13   ...
row2    val21   val22   val23   ...
...
</programlisting>
    The <function>crosstab</function> function takes a text parameter that is an SQL
    query producing raw data formatted in the first way, and produces a table
    formatted in the second way.
   </para>

   <para>
    The <parameter>sql</parameter> parameter is an SQL statement that produces
    the