JPQL Query on repository for non-related entities

Question

I am trying to make a JPQL request on a @Query from a repository(extends CrudRepository) for the following strucure:

@Entity 
@Table(name="Campaign")
public class Campaign {

 @Id
 @GeneratedValue(strategy=GenerationType.AUTO)
 @Column(columnDefinition = "int(11)")
 private Long id; 
...
 private String displayName;
 private String smrtProject;
...}

and

@Entity 
@Table(name="CampaignFact")
public class CampaignFact{
 @Id
 @GeneratedValue(strategy=GenerationType.AUTO)
 @Column(columnDefinition = "int(11)")
 private Long id;

 @ManyToOne(fetch = FetchType.EAGER)
 @JoinColumn(name = "campaignId")
 private Campaign campaign;

 @ManyToOne(fetch = FetchType.EAGER)
 @JoinColumn(name = "callCenterId")
 private CallCenter callCenter;
...}

What I am trying to query is fetching all campaigns related to a callcenter by callCenterId.

So far I am using a native query (MySql) that resumes well that I am try to do:

@Query(value = "SELECT c.* FROM CampaignFact cf Inner JOIN Campaign c ON c.id = cf.campaignId WHERE cf.callCenterId = ?1", nativeQuery = true)
List<Campaign> findByCallCenterIdNative(Long callCenterId);

So to resume how could re-write this SQL in JPQL? PS: I am working in this repository:

public interface CampaignRepository extends CrudRepository<Campaign, Long> 

Answer 1

Since you want CampaignFact so you need to have CampaignFactRepository and method definition will be like below:

List<CampaignFact> findByCampaign_idAndCallCenter_id(Long callCenterId);

I did not run it as I do not have DB but creating correct method name should make correct SQL call. Reference Spring Docs

Also you can check Spring Data JPA Tutorial