问题描述
当我在映射表中有许多额外关系的情况下有一个额外的列时，我在保存记录时遇到了问题.有关详细信息，请参见下面.
I am facing problem while saving a record when i have an extra column in the mapping table in case of manytomany relationship. Please see below for details.
UserAccount和BankAccounts之间存在许多关系.除了User和BankAccount表的主键之外，user_bankaccounts的映射表还有一个名为user_type的额外列.但是，当我尝试保存银行帐户记录时，映射表数据未插入到user_bankaccount表中.仅插入银行帐户表.我相信我自己不应该更新映射表，休眠将自动更新相应的映射表.
There is manytomany relationship between User and BankAccounts. The mapping table for user_bankaccounts has an extra column called user_type, apart from the primary keys of User and BankAccount table. However, when i try to save a bank account record, mapping table data is not inserted in the user_bankaccount table. Only bankaccount table is inserted. I believe i should not update the mapping table myself and hibernate will update the corresponding mapping table automatically.
@Entity
@Table(name = "Users")
public class User implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int userId;
@OneToMany(mappedBy = "user", fetch = FetchType.EAGER)
private Set<UserBankAccounts> userBankSet = new HashSet<UserBankAccounts>();
}
@Entity
@Table(name = "bankaccounts")
public class BankAccount implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "bank_account_id")
private int accountId;
@OneToMany(mappedBy = "bankAccounts", fetch = FetchType.EAGER)
private List<UserBankAccounts> userBankList = new ArrayList<UserBankAccounts>();
}
@Entity
@Table(name = "user_bankaccount")
@IdClass(UserBankAccountAssociationId.class)
public class UserBankAccounts {
@Id
@Column(name = "user_id", insertable = false, updatable = false)
private int userId;
@Id
@Column(name = "bank_account_id", insertable = false, updatable = false)
private int accountId;
@Column(name = "user_type")
private String userType;
@ManyToOne
@JoinColumn(name="user_id")
private User user;
@ManyToOne
@JoinColumn(name="bank_account_id")
private BankAccount bankAccounts;
}
public class UserBankAccountAssociationId implements Serializable {
private int userId;
private int accountId;
}
测试方法
@Test
@Loggable(value = LogLevel.DEBUG)
public void addBankAccount() {
Bank bank = bankdao.getBankByName("bank name").get(0);
User u1 = userdao.getUserByName("xxx", "yyy").get(0);
BankAccount ba = new BankAccount();
ba.setAccountType("Savings");
ba.setBank(bank);
ba.setBranch("xxx");
ba.setAccountNumber("112233445566");
ba.setOpMode("xxx");
UserBankAccounts userBankAcct = new UserBankAccounts();
userBankAcct.setUser(u1);
userBankAcct.setBankAccounts(ba);
userBankAcct.setUserId(u1.getUserId());
userBankAcct.setAccountId(ba.getAccountId());
userBankAcct.setUserType("Primary User");
u1.getUserBankSet().add(userBankAcct);
ba.getUserBankList().add(userBankAcct);
bankAccountDAO.addBankAccount(ba);
}
推荐答案
我认为您对Idclass注释有误解.您应该看一下这个例子. 多对多示例
I think you have a misunderstanding of Idclass annotation. You should take a look at this example. Many To Many sample
如果您使用示例中的映射，则hibernate将自动为您创建一个联接表.但是，如果要在联接表上增加额外的列(例如user_type)，则必须自己创建联接表.
If you use a mapping as in the example, hibernate will automatically create a join table for you. However, if you want to have extra columns on your join table (like user_type), you have to create join table yourself.
@Entity
@Table(name = "user_bankaccount")
public class UserBankAccounts {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private Long id;
@Column(name = "user_type")
private String userType;
@ManyToOne
@JoinColumn(name="user_id")
private User user;
@ManyToOne
@JoinColumn(name="bank_account_id")
private BankAccount bankAccounts;
}
不需要userId和accountId字段.并且，如果您希望在银行帐户或用户持续存在时保存/删除/更新用户银行帐户，请在您的银行帐户或用户实体中使用级联注释.
There is no need for userId and accountId fields. And if you want userbankaccounts to be saved/deleted/updated when bankaccount or user persisted, use cascade annotation in your bankaccount or user entities.
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