filtered to only show user and system indexes respectively.
  </para>

  <table id="pg-stat-all-indexes-view" xreflabel="pg_stat_all_indexes">
   <title><structname>pg_stat_all_indexes</structname> View</title>
   <tgroup cols="1">
    <thead>
     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       Column Type
      </para>
      <para>
       Description
      </para></entry>
     </row>
    </thead>

    <tbody>
     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relid</structfield> <type>oid</type>
      </para>
      <para>
       OID of the table for this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>indexrelid</structfield> <type>oid</type>
      </para>
      <para>
       OID of this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>schemaname</structfield> <type>name</type>
      </para>
      <para>
       Name of the schema this index is in
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>relname</structfield> <type>name</type>
      </para>
      <para>
       Name of the table for this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>indexrelname</structfield> <type>name</type>
      </para>
      <para>
       Name of this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>idx_scan</structfield> <type>bigint</type>
      </para>
      <para>
       Number of index scans initiated on this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>last_idx_scan</structfield> <type>timestamp with time zone</type>
      </para>
      <para>
       The time of the last scan on this index, based on the
       most recent transaction stop time
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>idx_tup_read</structfield> <type>bigint</type>
      </para>
      <para>
       Number of index entries returned by scans on this index
      </para></entry>
     </row>

     <row>
      <entry role="catalog_table_entry"><para role="column_definition">
       <structfield>idx_tup_fetch</structfield> <type>bigint</type>
      </para>
      <para>
       Number of live table rows fetched by simple index scans using this
       index
      </para></entry>
     </row>
    </tbody>
   </tgroup>
  </table>

  <para>
   Indexes can be used by simple index scans, <quote>bitmap</quote> index scans,
   and the optimizer.  In a bitmap scan
   the output of several indexes can be combined via AND or OR rules,
   so it is difficult to associate individual heap row fetches
   with specific indexes when a bitmap scan is used.  Therefore, a bitmap
   scan increments the
   <structname>pg_stat_all_indexes</structname>.<structfield>idx_tup_read</structfield>
   count(s) for the index(es) it uses, and it increments the
   <structname>pg_stat_all_tables</structname>.<structfield>idx_tup_fetch</structfield>
   count for the table, but it does not affect
   <structname>pg_stat_all_indexes</structname>.<structfield>idx_tup_fetch</structfield>.
   The optimizer also accesses indexes to check for supplied constants
   whose values are outside the recorded range of the optimizer statistics
   because the optimizer statistics might be stale.
  </para>

  <note>
   <para>
    The <structfield>idx_tup_read</structfield> and <structfield>idx_tup_fetch</structfield> counts
    can be different even without any use of bitmap scans,
    because <structfield>idx_tup_read</structfield>