内部连接上的休眠选择错误

Question

我在使用 hibernate/HQL 时遇到了一个错误

我的表是 table1(id, data)，其中 id -> 主键和 table2(id, anotherdata)，其中 id -> 对 table1.id 的外键引用。

头等舱->

@Entity
@Table(name = "table1")
public class Table1 {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

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

    @OneToOne
    private Table2 table2;
    //construct, get, set
}

二等->

@Entity
@Table(name = "table2")
public class Table2 {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

    @Column(name = "anotherdata")
    private String data;
    //get, set, construct
}

HQL 查询是 SELECT t1.id, t1.data, t2.data FROM Table1 as t1 JOIN t1.table2 as t2

休眠日志：select t1.id, t1.data, t2.anotherdata from table1 t1 inner join table2 on t1.t2_id = t2.id

这会导致错误ERROR: column t1.t2__id does not exist

在这个语句的末尾“on t1.t2_id = t2.id”我应该有“on t1.id = t2.id”（纯sql）

我该如何解决这个问题？将感谢您的所有回答！

Answer 1

您的查询是正确的，但您应该更改映射：

@Entity
@Table(name = "table1")
public class Table1 {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

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

    @OneToOne(mappedBy = "table1", cascade = CascadeType.ALL)
    private Table2 table2;
    //construct, get, set
}



@Entity
@Table(name = "table2")
public class Table2 {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

    @Column(name = "anotherdata")
    private String data;
    //get, set, construct

    @OneToOne
    @PrimaryKeyJoinColumn
    private Table1 table1;
}