ck cache hits by the statement
      </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
       <code class="structfield">shared_blks_read</code> <code class="type">bigint</code>
      </p>
      <p>
       Total number of shared blocks read by the statement
      </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
       <code class="structfield">shared_blks_dirtied</code> <code class="type">bigint</code>
      </p>
      <p>
       Total number of sh