嗯，您遇到的基本问题是根据列而不是实体进行思考，尽管由于问题有点棘手，所以这可能是不公平的陈述。基本问题是如何将实体作为复合键的一部分包含在内，我在这里找到了答案：如何在JPA中创建包含@ManyToOne属性作为@EmbeddedId的复合主键？。设备：
@Entity
@Table(name = "devices")
public class Device
{
@Id
@Column(name = "device_nbr")
private Long number;
@Column(name = "device_id", length = 20)
private String deviceid;
@ManyToOne(fetch=FetchType.EAGER, cascade=CascadeType.ALL)
@JoinColumns({@JoinColumn(name="dev_type", referencedColumnName="dev_type"), @JoinColumn(name="model_nbr", referencedColumnName="model_nbr")})
private DeviceModel deviceModel;
// This creates a foreign key constraint, but otherwise doesn't function
// deviceType must be accessed through deviceModel
// note, it can be used for explicit selects, e.g., "select d.deviceType from Device d"
@OneToOne(fetch=FetchType.EAGER, cascade=CascadeType.ALL)
@JoinColumn(name="dev_type", referencedColumnName="dev_type", insertable=false, updatable=false)
private DeviceType deviceType;
@Column(name = "unit_addr", length = 32)
private String unitAddress;
设备型号：
@Entity
@Table(name = "devmodels")
public class DeviceModel
{
@EmbeddedId
private DeviceModelId id;
@ManyToOne(fetch=FetchType.EAGER, cascade=CascadeType.ALL)
@JoinColumn(name="dev_type")
@MapsId("deviceType")
private DeviceType deviceType;
@Column(name = "model_desc", length=20)
private String description;
DeviceModelId：
@Embeddable
public class DeviceModelId implements Serializable
{
private static final long serialVersionUID = -8173857210615808268L;
private Integer deviceType;
@Column(name="model_nbr")
private Integer modelNumber;
请注意，我使用@Embeddable和@EmbeddedId。它只是更新的，我已经阅读了JPA提供程序的评论，它比首选@IdClass。我认为这也使列命名更容易一些，但我不记得了。
设备类型：
@Entity
@Table(name = "devtypes")
public class DeviceType
{
@Id
@GeneratedValue
@Column(name = "dev_type")
private Integer deviceType;
@Column(name = "dev_desc", length = 16)
private String description;
诀窍是@MapsId在DeviceModel。这样就可以在CompositeKey中使用实体。该字段上的@JoinColumn启用了该字段的命名。使用它的唯一技巧是手动创建DeviceTypeId：
DeviceModel model = new DeviceModel();
DeviceModelId modelId = new DeviceModelId();
modelId.setModelNumber(654321);
// have to have a DeviceType to create a DeviceModel
model.setDeviceType(type);
model.setId(modelId);
这将创建以下模式，该模式似乎与您的模式匹配。
create table devices (device_nbr bigint not null, device_id varchar(20), unit_addr varchar(32), dev_type integer, model_nbr integer, primary key (device_nbr))
create table devmodels (dev_type integer not null, model_nbr integer not null, model_desc varchar(20), primary key (dev_type, model_nbr))
create table devtypes (dev_type integer not null, dev_desc varchar(16), primary key (dev_type))
alter table devices add constraint FK8q0a886v04gg0qv261x1b2qrf foreign key (dev_type, model_nbr) references devmodels
alter table devices add constraint FKb72a7hq5phwjtbhaglobdkgji foreign key (dev_type) references devtypes
alter table devmodels add constraint FK4xlwyd2gwpbs4g4hdckyb11oj foreign key (dev_type) references devtypes
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