JPA Left Join IS NULL-Bedingung funktioniert nicht

Question

Ich habe Benutzer- und Employee-Tabellen für MySQL, und in der User-Tabelle gibt es employeeId als Fremdschlüssel.

Jetzt muss ich Mitarbeiter, die keinen Benutzer haben.

Ich schreibe diese SQL in MySQL Workbench, das funktioniert genau, wie ich will:

SELECT * FROM HUMANRESOURCE.EMPLOYEE E LEFT JOIN AUTHORIZE.USER U 
             ON U.EMPLOYEEOBJID = E.OBJID 
             WHERE U.EMPLOYEEOBJID is NULL; 

Aber wenn ich versuche, diese SQL als JPA-Abfrage zu implementieren, es gibt nichts zurück. Hier ist JPA Abfrage:

Query query = em.createQuery("SELECT e FROM Employee e LEFT JOIN User u 
             WHERE u.employee.objid = e.objid 
             AND u.employee IS NULL"); 

Und hier ist wirklich arbeiten JPA Abfrage, die ich für Mitarbeiter, die haben immer Benutzer:

Query query = em.createQuery("SELECT e FROM Employee e INNER JOIN User u 
             WHERE u.employee.objid = e.objid"); 

Was mache ich falsch hier?

Update für Entitätsklassen:

Base.java

package com.kadir.entity; 

import java.math.BigInteger; 
import java.sql.Timestamp; 
import java.util.Date; 

import javax.persistence.Cacheable; 
import javax.persistence.Column; 
import javax.persistence.GeneratedValue; 
import javax.persistence.GenerationType; 
import javax.persistence.Id; 
import javax.persistence.MappedSuperclass; 
import javax.persistence.Version; 


@Cacheable 
@MappedSuperclass 
public abstract class Base { 
    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    @Column(name = "OBJID") 
    private BigInteger objid; 

    @Column(name = "CREATEDBY") 
    private String createdby; 

    @Column(name = "CREATEDDATE") 
    private Timestamp createddate; 

    @Version 
    @Column(name = "ROWVERSION") 
    private Integer rowversion; 

    @Column(name = "UPDATEDBY") 
    private String updatedby; 

    @Column(name = "UPDATEDDATE") 
    private Timestamp updateddate; 

    @Column(name = "ARCHIVED", columnDefinition = "int default 0") 
    private int archived; 

    public BigInteger getObjid() { 
     return this.objid; 
    } 

    public void setObjid(BigInteger objid) { 
     this.objid = objid; 
    } 

    public String getCreatedby() { 
     return this.createdby; 
    } 

    public void setCreatedby(String createdby) { 
     this.createdby = createdby; 
    } 

    public Date getCreateddate() { 
     return this.createddate; 
    } 

    public void setCreateddate(Timestamp createddate) { 
     this.createddate = createddate; 
    } 

    public Integer getRowversion() { 
     return this.rowversion; 
    } 

    public void setRowversion(Integer rowversion) { 
     this.rowversion = rowversion; 
    } 

    public String getUpdatedby() { 
     return this.updatedby; 
    } 

    public void setUpdatedby(String updatedby) { 
     this.updatedby = updatedby; 
    } 

    public Timestamp getUpdateddate() { 
     return this.updateddate; 
    } 

    public void setUpdateddate(Timestamp updateddate) { 
     this.updateddate = updateddate; 
    } 

    public int getArchived() { 
     return archived; 
    } 

    public void setArchived(int archived) { 
     this.archived = archived; 
    } 
} 

Employee.java

package com.kadir.entity.humanresource; 

import com.kadir.entity.corporation.Company; 
import com.kadir.entity.Base; 

import java.io.Serializable; 

import javax.persistence.*; 


/** 
* The persistent class for the EMPLOYEE database table. 
* 
*/ 
@Cacheable 
@Entity 
@Table(name = "EMPLOYEE", schema = "HUMANRESOURCE") 
@NamedQuery(name = "Employee.findAll", query = "SELECT e FROM Employee e") 
public class Employee extends Base implements Serializable { 
    private static final long serialVersionUID = 1L; 

    @ManyToOne 
    @JoinColumn(name = "COMPANYOBJID") 
    private Company company; 

    @Column(name = "FIRSTNAME") 
    private String firstname; 

    @Column(name = "GENDER") 
    private int gender; 

    @Column(name = "EMAIL") 
    private String email; 

    @Column(name = "PHONE") 
    private String phone; 

    @Column(name = "LASTNAME") 
    private String lastname; 

    public Employee() { 
    } 

    public Company getCompany() { 
     return this.company; 
    } 

    public void setCompany(Company company) { 
     this.company = company; 
    } 

    public String getFirstname() { 
     return this.firstname; 
    } 

    public void setFirstname(String firstname) { 
     this.firstname = firstname; 
    } 

    public int getGender() { 
     return this.gender; 
    } 

    public void setGender(int gender) { 
     this.gender = gender; 
    } 

    public String getEmail() { 
     return this.email; 
    } 

    public void setEmail(String email) { 
     this.email = email; 
    } 

    public String getPhone() { 
     return this.phone; 
    } 

    public void setPhone(String phone) { 
     this.phone = phone; 
    } 

    public String getLastname() { 
     return this.lastname; 
    } 

    public void setLastname(String lastname) { 
     this.lastname = lastname; 
    } 

} 

User.java

package com.kadir.entity.authorize; 

import com.kadir.entity.Employee; 
import com.kadir.entity.Base; 
import java.io.Serializable; 
import javax.persistence.*; 


import java.util.List; 


/** 
* The persistent class for the USER database table. 
* 
*/ 
@Cacheable 
@Entity 
@Table(name="USER", schema="AUTHORIZE") 
@NamedQuery(name="User.findAll", query="SELECT u FROM User u") 
public class User extends Base implements Serializable { 
    private static final long serialVersionUID = 1L; 

    @OneToOne 
    @JoinColumn(name="EMPLOYEEOBJID") 
    private Employee employee; 

    @Column(name="NAME") 
    private String name; 

    @Column(name="PASSWORD") 
    private String password; 

    public User() { 
    } 

    public Employee getEmployee() { 
     return this.employee; 
    } 

    public void setEmployee(Employee employee) { 
     this.employee = employee; 
    } 

    public String getName() { 
     return this.name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public String getPassword() { 
     return this.password; 
    } 

    public void setPassword(String password) { 
     this.password = password; 
    } 

} 

Answer 1

Eclipse hat Unterstützung für die ON clause, so versuchen Sie existieren und eine Unterabfrage verwenden, können mit

"SELECT e FROM Employee e LEFT JOIN User u on u.employee = e WHERE u.employee IS NULL" 

Sie auch:

"select e from Employee e where not exists (select 1 from User u where u.employee = e)"