 <sect1 id="functions-tid">
  <title>TID Functions</title>

  <indexterm zone="functions-tid">
   <primary>TID</primary>
   <secondary>functions</secondary>
  </indexterm>

  <indexterm>
   <primary>tid_block</primary>
  </indexterm>

  <indexterm>
   <primary>tid_offset</primary>
  </indexterm>

  <para>
   <xref linkend="functions-tid-table"/> lists functions for
   the <type>tid</type> data type (tuple identifier).
  </para>

  <table id="functions-tid-table">
   <title><acronym>TID</acronym> Functions</title>
   <tgroup cols="1">
    <thead>
     <row>
      <entry role="func_table_entry"><para role="func_signature">
       Function
      </para>
      <para>
       Description
      </para>
      <para>
       Example(s)
      </para></entry>
     </row>
    </thead>

    <tbody>
     <row>
      <entry role="func_table_entry"><para role="func_signature">
       <function>tid_block</function> ( <type>tid</type> )
       <returnvalue>bigint</returnvalue>
      </para>
      <para>
       Extracts the block number from a tuple identifier.
      </para>
      <para>
       <literal>tid_block('(42,7)'::tid)</literal>
       <returnvalue>42</returnvalue>
      </para></entry>
     </row>

     <row>
      <entry role="func_table_entry"><para role="func_signature">
       <function>tid_offset</function> ( <type>tid</type> )
       <returnvalue>integer</returnvalue>
      </para>
      <para>
       Extracts the tuple offset within the block from a tuple identifier.
      </para>
      <para>
       <literal>tid_offset('(42,7)'::tid)</literal>
       <returnvalue>7</returnvalue>
      </para></entry>
     </row>
    </tbody>
   </tgroup>
  </table>
 </sect1>
