EntityNotFoundException LEFT JOIN JPA - Hibernate

Question

Exception in thread "main" javax.persistence.EntityNotFoundException: Unable to find CNPJ with id 00001388000307

I was reading jpa documentation, i read that this exception is thrown when it try to accesse(by the method getReference of EntityManger interface) and the entity doesn't exists

Thrown by the persistence provider when an entity reference obtained by EntityManager.getReference is accessed but the entity does not exist.

I have this entitys: Salesman e CNPJ . It's possible that exists many salesmen with the same CNPJ, in other words, a relationship @ManyToOne .

This relationship is working, OK.

But, when i try to execute the query

select r from Salesman r join fetch r.yearMonth left join fetch r.cnpj

to bring the salesmen with its yearMonth(it's working!) relationship and its CNPJ relationship, throws the Exception, when i try to do a LEFT JOIN, that i mentioned.

When i don't execute a LEFT JOIN , works great, all Salesmen with his CNPJs and nothin of Exceptions, BUUUUT, some salesmen don't have CNPJ nad i have to bring them too, there's a necessity to do a LEFT JOIN .

@Entity
public class Salesman{

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

    @JoinColumn(name = "year_month")
    @ManyToOne
    private YearMonth yearMonth;

    private String cnpjS;

    @JoinColumn(name = "cnpj")
    @ManyToOne
    private CNPJ cnpj;

    public AnoMes getYearMonth() {
        return yearMonth;
    }

    public CNPJ getCnpj() {
        return cnpj;
    }

}

@Entity
public class CNPJ {

    @Id
    @Column(name = "CCG", length = 14)
    private String ccg;

    public String getCcg() {
        return ccg;
    }
}

The select generated by Hibernate:

select *
from salesman s
inner join yearmonth y on s.ano_mes = y.id 
left outer join cnpj c on s.cnpjS = c.CCG

This consult returns this values, rcnpj is cnpj from Salesman and bcnpj is from CNPJ. Some Salesmen came with CNPJ NULL, i think that it's the problem. I don't think so.

Answer 1

Try to enable hibernate sql logging with <property name="show_sql">true</property> to see how real query (native, invoked on db) looks like, maybe there is a inner join after hibernate processing.

To change it you can try @Column(nullable=true) annotation for your relationship or @Fetch(FetchMode.SELECT) to see how real query will change.

---

The reason is that you have a reference to cnpj with ID 00001388000307, but such row of cnpj doesn't exist.

You can try to use @NotFound(action=NotFoundAction.IGNORE) to skip such error, but it is recommended to fix your database of handle a exception.

Answer 2

You are using the cnpj column on the table Salesman as both a foreign key and a value column. In that case @staszko032's suggestion using @NotFound(action=NotFoundAction.IGNORE) looks like will work as you expect

But I think you should refactor your model if possible. You could create a CNPJ entity always, in that case you won't have Salesman without a realation to CNPJ and could use INNER JOIN, or use 2 columns, one that will be used when the Salesman doesn't have a concrete related CNPJ (the value as string) and the other when it has (the foreign key)