protected function _setLimit()
    {
        if (
            is_null($this->_sql->getLimit()) ||
            intval($this->_sql->getLimit()) < 1
        ) {
            return $this;
        }

        if ($this->_sql->getOffset() > 0) {
            return $this->_setLimitWithOffset();
        }
        return  $this->_setSimpleLimit();
    }