'my_table'::regclass AND attnum &gt; 0</userinput>
-&gt; <userinput>ORDER BY attnum</userinput>
-&gt; <userinput>\gexec</userinput>
CREATE INDEX
CREATE INDEX
CREATE INDEX
CREATE INDEX
</programlisting>
        </para>

        <para>
         The generated queries are executed in the order in which the rows
         are returned, and left-to-right within each row if there is more
         than one column.  NULL fields are ignored.  The generated queries
         are sent literally to the server for processing, so they cannot be
         <application>psql</application> meta-commands nor contain <application>psql</application>
         variable references.  If any individual query fails, execution of
         the remaining queries continues
         unless <varname>ON_ERROR_STOP</varname> is set.  Execution of each
         query is subject to <varname>ECHO</varname> processing.
         (Setting <varname>ECHO</varname> to <literal>all</literal>
         or <literal>queries</literal> is often advisable when
         using <command>\gexec</command>.)  Query logging, single-step mode,
         timing, and other query execution features apply to each generated
         query as well.
        </para>
        <para>
         If the current query buffer is empty, the most recently sent query
         is re-executed instead.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry id="app-psql-meta-command-gset">
        <term><literal>\gset [ <replaceable class="parameter">prefix</replaceable> ]</literal></term>

        <listitem>
        <para>
         Sends the current query buffer to the server and stores the
         query's output into <application>psql</application> variables
         (see <xref linkend="app-psql-variables"/> below).
         The query to be executed must return exactly one row.  Each column of
         the row is stored into a separate variable, named the same as the
         column.  For example:
<programlisting>
=&gt; <userinput>SELECT 'hello' AS var1, 10 AS var2</userinput>
-&gt; <userinput>\gset</userinput>
=&gt; <userinput>\echo :var1 :var2</userinput>
hello 10
</programlisting>
        </para>
        <para>
         If you specify a <replaceable class="parameter">prefix</replaceable>,
         that string is prepended to the query's column names to create the
         variable names to use:
<programlisting>
=&gt; <userinput>SELECT 'hello' AS var1, 10 AS var2</userinput>
-&gt; <userinput>\gset result_</userinput>
=&gt; <userinput>\echo :result_var1 :result_var2</userinput>
hello 10
</programlisting>
        </para>
        <para>
         If a column result is NULL, the corresponding variable is unset
         rather than being set.
        </para>
        <para>
         If the query fails or does not return one row,
         no variables are changed.
        </para>
        <para>
         If the current query buffer is empty, the most recently sent query
         is re-executed instead.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry id="app-psql-meta-command-gx">
        <term><literal>\gx [ (<replaceable class="parameter">option</replaceable>=<replaceable class="parameter">value</replaceable> [...]) ] [ <replaceable class="parameter">filename</replaceable> ]</literal></term>
        <term><literal>\gx [ (<replaceable class="parameter">option</replaceable>=<replaceable class="parameter">value</replaceable> [...]) ] [ |<replaceable class="parameter">command</replaceable> ]</literal></term>
        <listitem>
        <para>
        <literal>\gx</literal> is equivalent to <literal>\g</literal>, except
        that it forces expanded output mode for this query, as
        if <literal>expanded=on</literal> were included in the list of
        <literal>\pset</literal> options.  See also <literal>\x</literal>.
        </para>
        </listitem>
      </varlistentry>


      <varlistentry id="app-psql-meta-command-help">
        <term><literal>\h</literal>