Wie verbinde ich mehrere Spring Data JPA-Repositorys mit verschiedenen Datenquellen in Spring Boot?

<code class="java">@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "customerEntityManager",
        transactionManagerRef = "customerTransactionManager",
        basePackages = {"com.mm.repository.customer"})
public class CustomerDbConfig {

    // Bean definitions for data source, entity manager factory, and transaction manager for first data source
}</code>

<code class="java">@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "orderEntityManager",
        transactionManagerRef = "orderTransactionManager",
        basePackages = {"com.mm.repository.order"})
public class OrderDbConfig {

    // Bean definitions for data source, entity manager factory, and transaction manager for second data source
}</code>

<code class="java">@Entity
@Table(name = "customer")
public class Customer {

    // ...
}

@Entity
@Table(name = "order")
public class Order {

    // ...
}</code>

<code class="java">public interface CustomerRepository extends JpaRepository&lt;Customer, Integer&gt; {}

public interface OrderRepository extends JpaRepository&lt;Order, Integer&gt; {}</code>

<code class="java">@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}</code>

<code class="properties"># Customer Data Source
spring.datasource.primary.url=...
spring.datasource.primary.username=...
spring.datasource.primary.password=...
spring.datasource.primary.driverClassName=...

# Order Data Source
spring.datasource.secondary.url=...
spring.datasource.secondary.username=...
spring.datasource.secondary.password=...
spring.datasource.secondary.driverClassName=...</code>