without notice.
    </para>

    <variablelist>
     <varlistentry>
      <term><option>-f</option> <literal>{ s | i | o | b | t | n | m | h }</literal></term>
      <listitem>
       <para>
        Forbids the use of particular scan and join methods:
        <literal>s</literal> and <literal>i</literal>
        disable sequential and index scans respectively,
        <literal>o</literal>, <literal>b</literal> and <literal>t</literal>
        disable index-only scans, bitmap index scans, and TID scans
        respectively, while
        <literal>n</literal>, <literal>m</literal>, and <literal>h</literal>
        disable nested-loop, merge and hash joins respectively.
       </para>

       <para>
        Neither sequential scans nor nested-loop joins can be disabled
        completely; the <literal>-fs</literal> and
        <literal>-fn</literal> options simply discourage the optimizer
        from using those plan types if it has any other alternative.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-O</option></term>
      <listitem>
       <para>
        Allows the structure of system tables to be modified.  This is
        used by <command>initdb</command>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-P</option></term>
      <listitem>
       <para>
        Ignore system indexes when reading system tables, but still update
        the indexes when modifying the tables.  This is useful when
        recovering from damaged system indexes.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-t</option> <literal>pa[rser] | pl[anner] | e[xecutor]</literal></term>
      <listitem>
       <para>
        Print timing statistics for each query relating to each of the
        major system modules.  This option cannot be used together
        with the <option>-s</option> option.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-T</option></term>
      <listitem>
       <para>
        This option is for debugging problems that cause a server
        process to die abnormally.  The ordinary strategy in this
        situation is to notify all other server processes that they
        must terminate, by sending them <systemitem>SIGQUIT</systemitem>
        signals.  With this option, <systemitem>SIGABRT</systemitem>
        will be sent instead, resulting in production of core dump files.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-v</option> <replaceable class="parameter">protocol</replaceable></term>
      <listitem>
       <para>
        Specifies the version number of the frontend/backend protocol
        to be used for a particular session.  This option is for
        internal use only.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><option>-W</option> <replaceable class="parameter">seconds</replaceable></term>
      <listitem>
       <para>
        A delay of this many seconds occurs when a new server process
        is started, after it conducts the authentication procedure.
        This is intended to give an opportunity to attach to the
        server process with a debugger.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
   </refsect2>

   <refsect2>
    <title>Options for Single-User Mode</title>

    <indexterm>
     <primary>single-user mode</primary>
    </indexterm>

    <para>
     The following options only apply to the single-user mode
     (see <xref linkend="app-postgres-single-user"/> below).
    </para>

    <variablelist>
     <varlistentry>
      <term><option>--single</option></term>
      <listitem>
       <para>
        Selects the single-user mode.  This must be the first argument
        on the command line.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry>
      <term><replaceable class="parameter">database</replaceable></term>