Question

我正在开发一个项目并使用Hibernate进行数据库交互。

我有两个表，一个是RESOURCE_PROFILE，第二个是PROJECT_MASTER。以下是DDL声明。

CREATE TABLE USER_PROFILE (
    FIRST_NAME VARCHAR(15) NOT NULL,
    MIDDLE_NAME VARCHAR(15),
    LAST_NAME VARCHAR(15) NOT NULL,
    EMAIL_ID VARCHAR(40) NOT NULL,
    USER_ID VARCHAR(40) NOT NULL,
    PASSWORD VARCHAR(1000) NOT NULL,
    ROLE VARCHAR(20),
    SUPERVISOR_ID VARCHAR(20),
    SUBMITTED_BY VARCHAR(20),
    SUBMITTED_DATE DATE,
    PRIMARY KEY (USER_ID)
);

CREATE TABLE PROJECT_MASTER (
    PROJECT_ID INT NOT NULL AUTO_INCREMENT,
    PROJECT_NAME VARCHAR(50) NOT NULL,
    PROJECT_NUMBER VARCHAR(50) NOT NULL,
    START_DATE DATE,
    END_DATE DATE,
    PROJECT_MANAGER_ID VARCHAR(40) NOT NULL,
    PROJECT_SUPERVISOR_ID VARCHAR(40) NOT NULL,
    SUBMITTED_BY VARCHAR(40),
    SUBMITTED_DATE DATE,
    UPDATED_BY VARCHAR(40),
    PRIMARY KEY (PROJECT_ID),
    FOREIGN KEY (PROJECT_MANAGER_ID) REFERENCES USER_PROFILE(USER_ID),
    FOREIGN KEY (PROJECT_SUPERVISOR_ID) REFERENCES USER_PROFILE(USER_ID),
    FOREIGN KEY (SUBMITTED_BY) REFERENCES USER_PROFILE(USER_ID),
    FOREIGN KEY (UPDATED_BY) REFERENCES USER_PROFILE(USER_ID)
);

正如您在PROJECT_MASTER表中所看到的，我使用USER_ID(RESOURCE_PROFILE)作为PROJECT_MASTER表中多列的外键。下面是我为这两个表创建的实体类。我确信我在映射中做错了，你能帮助我并指出正确的方向吗？由于我将相同的外键用于多列，我该如何实现这种映射？

    @Entity
    @Table(name = "PROJECT_MASTER")
    public class ProjectMasterBean  {

      @Id
      @GeneratedValue
      @Column(name="PROJECT_ID")
      private int projectID;

      @Column(name="PROJECT_NAME")
      private String projectName;

      @Column(name="PROJECT_NUMBER")
      private String projectNumber;

      @Column(name="START_DATE")
      private Date startDate;

      @Column(name="END_DATE")
      private Date endDate;

      @ManyToOne
     @JoinColumn(name="USER_ID",insertable=false, updatable=false,
            nullable=false)
      private UserProfileBean projectManagerID;

      @ManyToOne
     @JoinColumn(name="USER_ID",insertable=false, updatable=false,
            nullable=false)
      private UserProfileBean projectSupervisorID;

      @ManyToOne
    @JoinColumn(name="USER_ID",insertable=false, updatable=false,
            nullable=false)
      private UserProfileBean submittedBy;
    }

      @Column(name="SUBMITTED_DATE")
      private Date submittedDate;

      @ManyToOne
    @JoinColumn(name="USER_ID",insertable=false, updatable=false,
            nullable=false)
      private UserProfileBean updatedBy;


     public class UserProfileBean  {
    @Id
      @Column(name="USER_ID")
      private String userID;

      @Column(name="FIRST_NAME")
      private String firstName;

      @Column(name="MIDDLE_NAME")
      private String middleName;

      @Column(name="LAST_NAME")
      private String lastName;

      @Column(name="EMAIL_ID")
      private String emailID;

      @Column(name="PASSWORD")
      private String password;

      @Column(name="ROLE")
      private String userRole;

      @Column(name="SUPERVISOR_ID")
      private String supervisorID;

      @Column(name="SUBMITTED_BY")
      private String submittedBy;

      @Column(name="SUBMITTED_DATE")
      private String submittedDate;
}

这是我得到的例外：

Hibernate：插入PROJECT_MASTER（PROJECT_NAME，PROJECT_NUMBER，START_DATE，END_DATE，SUBMITTED_BY，SUBMITTED_DATE，UPDATED_BY）值（？，？，？，？，？，？，？） 2013年9月12日下午8:46:20 org.apache.catalina.core.StandardWrapperValve调用严重：servlet操作的Servlet.service（）抛出异常

java.sql.SQLException: Field 'PROJECT_MANAGER_ID' doesn't have a default value
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1073)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3609)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3541)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2002)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2163)

Insert Query甚至没有这两列。这就是查询的方式。

Hibernate：插入PROJECT_MASTER（PROJECT_NAME，PROJECT_NUMBER，START_DATE，END_DATE，PROJECT_MANAGET_ID，PROJECT_SUPERVISOR_ID，SUBMITTED_BY，SUBMITTED_DATE，UPDATED_BY）值（？，？，？，？，？，？，？，？，？）

Answer 1

您已使用

创建了表格

CREATE TABLE PROJECT_MASTER（PROJECT_ID INT NOT NULL AUTO_INCREMENT， PROJECT_NAME VARCHAR（50）NOT NULL，PROJECT_NUMBER VARCHAR（50）NOT NULL，START_DATE DATE，END_DATE DATE， PROJECT_MANAGER_ID VARCHAR（40） NOT NULL ，PROJECT_SUPERVISOR_ID VARCHAR（40）NOT NULL，SUBMITTED_BY VARCHAR（40），SUBMITTED_DATE DATE，UPDATED_BY VARCHAR（40），PRIMARY KEY （PROJECT_ID）， FOREIGN KEY（PROJECT_MANAGER_ID）参考 USER_PROFILE（USER_ID），FOREIGN KEY（PROJECT_SUPERVISOR_ID）参考 USER_PROFILE（USER_ID），FOREIGN KEY（SUBMITTED_BY）参考 USER_PROFILE（USER_ID），FOREIGN KEY（UPDATED_BY）参考 USER_PROFILE（USER_ID））;

你让你的班级使用这个表。因为你没有NOT NULL字段的默认值，所以Hibernate会抱怨。从表中删除该列或在实体映射中添加关系。

更改为

@ManyToOne
@JoinColumn(name="PROJECT_MANAGER_ID ",insertable=false, updatable=false,
        nullable=false)
private UserProfileBean projectManagerID;

定义映射时的Hibernate异常

1 个答案: