查找列的Hibernate注释

Question

我有三张桌子: po_dtl和workbook_types。每个采购订单行(po_dtl)都将有"workbook_code“列来引用workbook_types。基本上，po_dtl.workbook_code只是workbook_types.workbook_code的查找代码。

简化的java类是

@Entity
@Table(name="po_dtl")
public class PurchaseOrderDtl {
    @Id
    @Column(name = "po_dtl_id")
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "po_dtl_s")
    @SequenceGenerator(name = "po_dtl_s", sequenceName = "po_dtl_s", allocationSize = 1, initialValue = 1)
    private long id;

    @Column(name = "price_base", length = 7)
    private int priceBase;

    // ??? What is the annotation for workbook_Types?
    private WorkbookType workbookType;

    ....
}

而workbook_types

@Entity
@Table(name = "workbook_types")
public class WorkbookType {

    @Id
    @Column(name = "workbook_code")
    private String workbookCode;

    @Column(name = "description", length = 255)
    private String description;

    @Column(name = "file_root_path", length = 255)
    private String fileRootPath;
    ....
}

我所使用的(没有hibernate)是：

• workbook_types.workbook_code包含字符串"wbook_finance“、"wbook_marketing”
• 每个po_dtl.workbook_code将包含"wbook_finance“或"wbook_marketing”
• workbook_types只包含带有唯一workbook_code的2行，而po_dtl将包含许多行，但每一行必须只包含"wbook_finance“或"wbook_marketing”。

谢谢

Answer 1

正如我理解您的问题一样，您需要@ManyToOne或使用enum，如果只在开发阶段添加了新的workbook_type。

@Entity
class Country  { //Country Dictionary

}

@Entity
class User {
    @ManyToOne
    private Country country;
}

请参阅How to design tables for data dictionary when using hibernate?