Spring Data Join with Specifications
Ich versuche, diese rohe SQL-Abfrage zu konvertieren:
select product.* from following_relationship
join product on following_relationship.following=product.owner_id
where following_relationship.owner=input
In Spring Data-Spezifikationen denke ich, dass mein Problem bisher darin besteht, diese Tabellen zu verknüpfen.
Hier ist meine aktuelle Konvertierung in Spezifikation:
protected Specification<Product> test(final User user){
return new Specification<Product>() {
@Override
public Predicate toPredicate(Root<Product> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
Join<FollowingRelationship,Product> pfJoin = query.from(FollowingRelationship.class).join("following");
pfJoin.on(cb.equal(pfJoin.get("following"),"owner"));
return query.where(cb.equal(pfJoin.get("following"),user)).getGroupRestriction();
}
};
}
Und ich erhalte diese Ausnahme:
Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessA
piUsageException: org.hibernate.hql.internal.ast.InvalidWithClauseException: with clause can only reference columns in the driving table
Ich möchte hinzufügen, dass ich neu bei Spring Framework bin, zum Beispiel, dass dies meine erste Anwendung für Spring ist, also entschuldige ich mich für die Anfängerfrage;)
Edit: hinzugefügte Entitäten Product, FollowingRelationShip
Entity
@JsonIdentityInfo(generator = ObjectIdGenerators.IntSequenceGenerator.class, property = "json_id_prop")
public class FollowingRelationship extends BaseEntity {
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "OWNER", referencedColumnName = "uuid")
private User owner;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "FOLLOWING", referencedColumnName = "uuid")
private User following;
public User getOwner() {
return owner;
}
public void setOwner(User owner) {
this.owner = owner;
}
public User getFollowing() {
return following;
}
public void setFollowing(User following) {
this.following = following;
}
}
@Entity
@Table(name = "product")
@JsonIdentityInfo(generator = ObjectIdGenerators.IntSequenceGenerator.class, property = "json_id_prop")
public class Product extends BaseEntity {
@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "OWNER_ID", referencedColumnName = "uuid")
private User owner;
@NotNull
private String name;
@NotNull
private String description;
@NotNull
private String price;
@NotNull
private String brand;
public String getName() {
return name;
, }
public void setName(String name) {
this.name = name;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
public String getBrand() {
return brand;
}
public void setBrand(String brand) {
this.brand = brand;
}
public User getOwner() {
return owner;
}
public void setOwner(User owner) {
this.owner = owner;
}
}
Product- und FollowingRelationShip-Entitäten haben keine explizite Beziehung, daher ist der Join bei meiner Implementierung über. Ich möchte erreichen, dass alle Produkte von allen Benutzern abgerufen werden, denen ein anderer Benutzer in den Spring-Datenspezifikationen folgt.