如何使用Symfony 4中未链接到实体的存储库？

interface MyCustomRepositoryInterface
{
    public function findCustomData(): array;
    // 其他自定义方法...
}

use Doctrine\DBAL\Connection;

class MyCustomRepository implements MyCustomRepositoryInterface
{
    private $connection;

    public function __construct(Connection $connection)
    {
        $this->connection = $connection;
    }

    public function findCustomData(): array
    {
        $sql = 'SELECT * FROM custom_table';
        $stmt = $this->connection->prepare($sql);
        $stmt->execute();

        return $stmt->fetchAll();
    }

    // 其他自定义方法的实现...
}

services:
    App\Repository\MyCustomRepositoryInterface:
        class: App\Repository\MyCustomRepository
        arguments:
            - '@doctrine.dbal.default_connection'

use App\Repository\MyCustomRepositoryInterface;

class MyService
{
    private $customRepository;

    public function __construct(MyCustomRepositoryInterface $customRepository)
    {
        $this->customRepository = $customRepository;
    }

    public function doSomething()
    {
        $customData = $this->customRepository->findCustomData();
        // 处理未链接到实体的数据...
    }
}