is index on filtering by <strong>store_id</strong> only, we
		expect to get <strong>4478</strong> per <strong>store_id</strong>. If we <i>also</i> filter by <strong>film_id</strong>, we expect to get fewer results:
		we only expect <strong>2</strong> rows per <strong>store_id</strong>:<strong>film_id</strong> combination.</li>
</ul>
</p>

<h3>ENVIRONMENT</h3>
Percona Server &gt;= 5.5.8-20.0 with <a href="http://www.percona.com/docs/wiki/percona-server:features:innodb_stats#innodb_index_stats">INNODB_INDEX_S