commas, to separate
    arguments.  Details are in
    <xref linkend="functions-binarystring-sql"/>.
    <productname>PostgreSQL</productname> also provides versions of these functions
    that use the regular function invocation syntax
    (see <xref linkend="functions-binarystring-other"/>).
   </para>

   <table id="functions-binarystring-sql">
    <title><acronym>SQL</acronym> Binary String Functions and Operators</title>
    <tgroup cols="1">
     <thead>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        Function/Operator
       </para>
       <para>
        Description
       </para>
       <para>
        Example(s)
       </para></entry>
      </row>
     </thead>

     <tbody>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm>
         <primary>binary string</primary>
         <secondary>concatenation</secondary>
        </indexterm>
        <type>bytea</type> <literal>||</literal> <type>bytea</type>
        <returnvalue>bytea</returnvalue>
       </para>
       <para>
        Concatenates the two binary strings.
       </para>
       <para>
        <literal>'\x123456'::bytea || '\x789a00bcde'::bytea</literal>
        <returnvalue>\x123456789a00bcde</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm>
         <primary>bit_length</primary>
        </indexterm>
        <function>bit_length</function> ( <type>bytea</type> )
        <returnvalue>integer</returnvalue>
       </para>
       <para>
        Returns number of bits in the binary string (8
        times the <function>octet_length</function>).
       </para>
       <para>
        <literal>bit_length('\x123456'::bytea)</literal>
        <returnvalue>24</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm>
         <primary>btrim</primary>
        </indexterm>
        <function>btrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
        <parameter>bytesremoved</parameter> <type>bytea</type> )
        <returnvalue>bytea</returnvalue>
       </para>
       <para>
        Removes the longest string containing only bytes appearing in
        <parameter>bytesremoved</parameter> from the start and end of
        <parameter>bytes</parameter>.
       </para>
       <para>
        <literal>btrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
        <returnvalue>\x345678</returnvalue>
       </para></entry>
      </row>

       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
          <primary>ltrim</primary>
         </indexterm>
         <function>ltrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
         <parameter>bytesremoved</parameter> <type>bytea</type> )
         <returnvalue>bytea</returnvalue>
        </para>
        <para>
         Removes the longest string containing only bytes appearing in
         <parameter>bytesremoved</parameter> from the start of
         <parameter>bytes</parameter>.
        </para>
        <para>
         <literal>ltrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
         <returnvalue>\x34567890</returnvalue>
        </para></entry>
       </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm>
         <primary>octet_length</primary>
        </indexterm>
        <function>octet_length</function> ( <type>bytea</type> )
        <returnvalue>integer</returnvalue>
       </para>
       <para>
        Returns number of bytes in the binary string.
       </para>
       <para>
        <literal>octet_length('\x123456'::bytea)</literal>
        <returnvalue>3</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <indexterm>
         <primary>overlay</primary>