Given following entities:
{code:java}
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@OneToOne(fetch = FetchType.LAZY)
@JoinColumn
private Chair chair;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public Chair getChair() {
return chair;
}
public void setChair(Chair chair) {
this.chair = chair;
}
}
{code}
{code:java}
@Entity
public class Chair {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@OneToOne( fetch = FetchType.LAZY, mappedBy = "chair")
private User user;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn
private Room room;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public Room getRoom() {
return room;
}
public void setRoom(Room room) {
this.room = room;
}
}
{code}
{code:java}
@Entity
public class Chair Room {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@ OneToOne OneToMany ( fetch = FetchType.LAZY, mappedBy = " chair room ")
private User user;
@ManyToOne(fetch List<Chair> chairs = FetchType.LAZY new ArrayList<>( ) ;
@JoinColumn
private Room room String name ;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public User getUser List<Chair> getChairs () {
return user chairs ;
}
public void setUser setChairs ( User user List<Chair> chairs ) {
this. user chairs = user chairs ;
}
public Room getRoom String getName () {
return room name ;
}
public void setRoom setName ( Room room String name ) {
this. room name = room name ;
}
}
{code}
When I try to retrieve all user and sort by room name, I get only users which have chair and room, but users without chair and room are not retrieved:
{code:java}
//work wrong, cross joins
Order order2 = cb.asc(root.get("chair").get("room").get("name"));
query.orderBy(order2);
users = entityManager.createQuery(query).
setHint("javax.persistence.fetchgraph", entityGraph).getResultList();
{code}
The following sql output printed, which contains unexpected cross join filtering null values:
{code:java}
select
user0_.id as id1_2_0_,
chair1_.id as id1_0_1_,
room2_.id as id1_1_2_,
user0_.chair_id as chair_id2_2_0_,
chair1_.room_id as room_id2_0_1_,
room2_.name as name2_1_2_
from
User user0_
left outer join
Chair chair1_
on user0_.chair_id=chair1_.id
left outer join
Room room2_
on chair1_.room_id=room2_.id cross
join
Room room4_
where
chair1_.room_id=room4_.id
order by
room4_.name asc
{code}
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