/** * Add filtering * * @return Mage_Reports_Model_Mysql4_Product_Downloads_Collection */ public function addFieldToFilter($field, $condition = null) { if ($field == 'link_title') { $conditionSql = $this->_getConditionSql('l.title', $condition); $this->getSelect()->where($conditionSql); } else { parent::addFieldToFilter($field, $condition); } return $this; }