connection example

$this->ids = $ids;
        $this->id = $ids->create($customerNumber);
        $this->firstName = 'Max';
        $this->lastName = 'Mustermann';
        $this->email = 'max@mustermann.com';
        $this->salutation = self::salutation($ids);

        $this->customerGroup($customerGroup);
        $this->defaultBillingAddress($billingAddress);
        $this->defaultShippingAddress($shippingAddress);

        $this->defaultPaymentMethodId = self::connection()->fetchOne(
            'SELECT LOWER(HEX(payment_method_id)) FROM sales_channel_payment_method JOIN payment_method ON sales_channel_payment_method.payment_method_id = payment_method.id WHERE sales_channel_id = :id AND payment_method.active = true LIMIT 1',
            ['id' => Uuid::fromHexToBytes($salesChannelId)]
        );
    }

    public function customerNumber(string $customerNumber): self
    {
        $this->customerNumber = $customerNumber;