Question

外键（FK300D262149997B：region_location [region]）的列数必须与引用的主键（region_location [region，location]）

1）。创建具有两列（主键和名称字段）的表“ region”。 2）。创建具有两列（主键和名称字段）的表“位置”。 3）。创建具有三列的表“ region_location”（主键，表“ region”的外键引用和表“ location”的外键引用）。 4）。创建具有三列（主键，名称字段，表'region_location'的外键引用和名称字段）的表'Area'。

/**
 * Region model
 */
@Entity
@Data
@EqualsAndHashCode(of = "id")
@Table(name = "region")
public class Region {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Integer id;

    @Column(name = "name")
    @NotNull
    @Size(min = 2, max = 255)
    private String name;

    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.MERGE)
    @JoinTable(name = "region_location", joinColumns = @JoinColumn(name = "region", referencedColumnName = "id"), inverseJoinColumns = @JoinColumn(name = "location", referencedColumnName = "id"))
    private Set<Location> location;    
}

/**
 * Location model
 */
@Entity
@Data
@ToString
@EqualsAndHashCode(of = "id")
@Table(name = "location")
public class Location {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Integer id;

    @Column(name = "name")
    @NotNull
    @Size(min = 2, max = 255)
    private String name;

    @Column(name = "pin_code")
    @NotNull
    @Min(value = 100000)
    @Max(value = 999999)
    private Integer pinCode;

    @ManyToMany(mappedBy = "location", fetch = FetchType.EAGER)
    private Set<Region> region;
}

/**
 * Region Location model
 */
@Entity
@Data
@ToString
@EqualsAndHashCode(of = "id")
@Table(name = "region_location")
public class RegionLocation {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Integer id;

    @ManyToOne(optional = false, fetch = FetchType.EAGER)
    @JoinColumn(name = "location")
    private Location location;

    @ManyToOne(optional = false, fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinColumn(name = "region")
    private Region region;    
}

/**
 * Area model
 */
@Entity
@Data
@ToString
@EqualsAndHashCode(of = "id")
@Table(name = "area")
public class Area {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Integer id;

    @Column(name = "name")   
    private String name;
    /**
    ** problem code
    **/
    @ManyToOne(optional = true, fetch = FetchType.EAGER)
    @JoinColumn(name = "region_location")
    private RegionLocation regionLocation;
}

当我尝试使用主类进行测试时，遇到诸如休眠映射错误之类的映射错误，例如外键（FK5110401A8398947：area [region_location_id]））必须具有与引用的主键相同的列数（region_location [region_id] ，location_id]）。

当我在区域中映射region_location表时，我知道区域表中会出现错误。如何使它起作用？

预先感谢

休眠映射问题：外键必须具有与引用的主键相同的列数

0 个答案: