| Given the following classes:
@Entity(name = "Genius")
public static class Genius extends Human {
private Long id;
public Genius() {
}
public Genius(Long id) {
this.id = id;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
}
@Entity(name = "Human")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public static class Human {
private Long realId;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "realId")
public Long getRealId() {
return realId;
}
public void setRealId(Long realId) {
this.realId = realId;
}
}
Executing the query: select count( h ) from Human h results in the following SQL:
select
count(idproperty0_.id) as col_0_0_
from
Human idproperty0_
Note that:
- idproperty0_.id is not the primary key column;
- Human does not have a property named id;
- count should be operating on the primary key, idproperty0_.realId.
The same select expression is generated using @Inheritance(strategy = InheritanceType.TABLE_PER_CLASS). When @Inheritance(strategy = InheritanceType.JOINED) is used, the generated SQL is:
select
count(idproperty0_1_.id) as col_0_0_
from
Human idproperty0_
In addition to using the wrong column, there is no table with alias idproperty0_1_. |
