getOrderBySQL example

$orderBySql = '';

        if ($assoc !== null && $assoc['type'] === ClassMetadata::MANY_TO_MANY) {
            $joinSql = $this->getSelectManyToManyJoinSQL($assoc);
        }

        if (isset($assoc['orderBy'])) {
            $orderBy = $assoc['orderBy'];
        }

        if ($orderBy) {
            $orderBySql = $this->getOrderBySQL($orderBy, $this->getSQLTableAlias($this->class->name));
        }

        $conditionSql = $criteria instanceof Criteria
            ? $this->getSelectConditionCriteriaSQL($criteria)
            : $this->getSelectConditionSQL($criteria, $assoc);

        switch ($lockMode) {
            case LockMode::PESSIMISTIC_READ:
                $lockSql = ' ' . $this->platform->getReadLockSQL();
                break;