Hibernate: How to fix "identifier of an instance altered from X to Y"?

Question

org.hibernate.HibernateException: identifier of an instance 
of org.cometd.hibernate.User altered from 12 to 3

in fact, my user table is really must dynamically change its value, my Java app is multithreaded. Any ideas how to fix it?

Answer 1

Are you changing the primary key value of a User object somewhere? You shouldn't do that. Check that your mapping for the primary key is correct.

What does your mapping XML file or mapping annotations look like?

Answer 2

在修改其 ID 字段之前，您必须从会话中分离您的实体

Answer 3

在我的情况下，hbm.xml 中的 PK 字段是“整数”类型，但在 bean 代码中它是long 。

Answer 4

In my case getters and setter names were different from Variable name.

private Long stockId;
    public Long getStockID() {
        return stockId;
    }
    public void setStockID(Long stockID) {
        this.stockId = stockID;
    }

where it should be

public Long getStockId() {
    return stockId;
}
public void setStockId(Long stockID) {
    this.stockId = stockID;
}

Answer 5

就我而言，我解决了将 @Id 字段类型从 long 更改为 Long 的问题。

Answer 6

Make sure you aren't trying to use the same User object more than once while changing the ID. In other words, if you were doing something in a batch type operation:

User user = new User();  // Using the same one over and over, won't work
List<Customer> customers = fetchCustomersFromSomeService();
for(Customer customer : customers) {
 // User user = new User(); <-- This would work, you get a new one each time
 user.setId(customer.getId());
 user.setName(customer.getName());
 saveUserToDB(user);
}

Answer 7

In my case, a template had a typo so instead of checking for equivalency (==) it was using an assignment equals (=).

So I changed the template logic from:

if (user1.id = user2.id) ...

to

if (user1.id == user2.id) ...

and now everything is fine. So, check your views as well!

Answer 8

In my particular case, this was caused by a method in my service implementation that needed the spring @Transactional(readOnly = true) annotation. Once I added that, the issue was resolved. Unusual though, it was just a select statement.

Answer 9

I was facing this issue, too.

The target table is a relation table, wiring two IDs from different tables. I have a UNIQUE constraint on the value combination, replacing the PK. When updating one of the values of a tuple, this error occured.

This is how the table looks like (MySQL):

CREATE TABLE my_relation_table (
  mrt_left_id BIGINT NOT NULL,
  mrt_right_id BIGINT NOT NULL,
  UNIQUE KEY uix_my_relation_table (mrt_left_id, mrt_right_id),
  FOREIGN KEY (mrt_left_id)
    REFERENCES left_table(lef_id),
  FOREIGN KEY (mrt_right_id)
    REFERENCES right_table(rig_id)
);

The Entity class for the RelationWithUnique entity looks basically like this:

@Entity
@IdClass(RelationWithUnique.class)
@Table(name = "my_relation_table")
public class RelationWithUnique implements Serializable {

  ...

  @Id
  @ManyToOne
  @JoinColumn(name = "mrt_left_id", referencedColumnName = "left_table.lef_id")
  private LeftTableEntity leftId;

  @Id
  @ManyToOne
  @JoinColumn(name = "mrt_right_id", referencedColumnName = "right_table.rig_id")
  private RightTableEntity rightId;

  ...

I fixed it by

// usually, we need to detach the object as we are updating the PK
// (rightId being part of the UNIQUE constraint) => PK
// but this would produce a duplicate entry, 
// therefore, we simply delete the old tuple and add the new one
final RelationWithUnique newRelation = new RelationWithUnique();
newRelation.setLeftId(oldRelation.getLeftId());
newRelation.setRightId(rightId);  // here, the value is updated actually
entityManager.remove(oldRelation);
entityManager.persist(newRelation);

Thanks a lot for the hint of the PK, I just missed it.

Answer 10

It is a problem in your update method. Just instance new User before you save changes and you will be fine. If you use mapping between DTO and Entity class, than do this before mapping.

I had this error also. I had User Object, trying to change his Location, Location was FK in User table. I solved this problem with

@Transactional
public void update(User input) throws Exception {

    User userDB = userRepository.findById(input.getUserId()).orElse(null);
    userDB.setLocation(new Location());
    userMapper.updateEntityFromDto(input, userDB);

    User user= userRepository.save(userDB);
}  

Answer 11

Also ran into this error message, but the root cause was of a different flavor from those referenced in the other answers here.

Generic answer: Make sure that once hibernate loads an entity, no code changes the primary key value in that object in any way. When hibernate flushes all changes back to the database, it throws this exception because the primary key changed. If you don't do it explicitly, look for places where this may happen unintentionally, perhaps on related entities that only have LAZY loading configured.

In my case, I am using a mapping framework (MapStruct) to update an entity. In the process, also other referenced entities were being updates as mapping frameworks tend to do that by default. I was later replacing the original entity with new one (in DB terms, changed the value of the foreign key to reference a different row in the related table), the primary key of the previously-referenced entity was already updated, and hibernate attempted to persist this update on flush.

Answer 12

Problem can be also in different types of object's PK ("User" in your case) and type you ask hibernate to get session.get(type, id); .

In my case error was identifier of an instance of <skipped> was altered from 16 to 32 . Object's PK type was Integer , hibernate was asked for Long type.

Answer 13

在我的情况下，这是因为属性在对象上很长，但在映射 xml 中是 int，这个异常应该更清楚

Answer 14

If you are using Spring MVC or Spring Boot try to avoid: @ModelAttribute("user") in one controoler, and in other controller model.addAttribute("user", userRepository.findOne(someId);

This situation can produce such error.

Answer 15

This is an old question, but I'm going to add the fix for my particular issue (Spring Boot, JPA using Hibernate, SQL Server 2014) since it doesn't exactly match the other answers included here:

I had a foreign key, eg my_id = '12345', but the value in the referenced column was my_id = '12345 '. It had an extra space at the end which hibernate didn't like. I removed the space, fixed the part of my code that was allowing this extra space, and everything works fine.

Answer 16

Faced the same Issue. I had an assosciation between 2 beans. In bean AI had defined the variable type as Integer and in bean BI had defined the same variable as Long. I changed both of them to Integer. This solved my issue.

Answer 17

I solve this by instancing a new instance of depending Object. For an example

instanceA.setInstanceB(new InstanceB());
instanceA.setInstanceB(YOUR NEW VALUE);

Answer 18

Well, i'm using thymeleaf and the objectA has the objectB. when I try to change the objectB this error appreas to me. then, I discover that I needed to mention the "id" and "version" fields in my .html because in it I had a select allowing to change the objectB.

Answer 19

In my case I had a primary key in the database that had an accent, but in other table its foreign key didn't have. For some reason, MySQL allowed this.

Answer 20

It looks like you have changed identifier of an instance of org.cometd.hibernate.User object menaged by JPA entity context. In this case create the new User entity object with appropriate id. And set it instead of the original User object.

Answer 21

Did you using multiple Transaction managers from the same service class. Like, if your project has two or more transaction configurations. If true, then at first separate them.

Answer 22

I got the issue when i tried fetching an existing DB entity, modified few fields and executed

session.save(entity)

instead of

session.merge(entity)

Since it is existing in the DB, when we should merge() instead of save()

Answer 23

您可能会修改获取实体的主键，然后尝试使用相同的事务保存以从现有记录中创建新记录。