Two id in hibernate table

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Two id in hibernate table

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#1 by (2 votes)

2

Is there a possibility of two fields being id in a hibernate table? I have two ids that need to be unique in pair on the table. But I do not know how to implement it.

java hibernate spring-boot

asked by anonymous 15.12.2017 / 00:25

1 answer

How does the life cycle dependency injection work? Using the def function

score 2 · Accepted Answer

You can do it using @EmbeddedId

You can do this:

@Embeddable
class ClassePrimeira implements Serializable {

@Id
Integer chaveUm;
@Id
Integer chaveDois;

// get’s e set’s  

}

@Entity
public class Classe {

@EmbeddedId
private ClassePrimeira id;
// get’s e set’s  
}

Annotation @Id , @IdClass , or @EmbeddedId for Composite Keys: When a primary key consists of multiple columns, we need a different strategy to group them together so that we can that the persistence tool manipulates key values as a single object. In this way, we need to create a class that represents this primary key. This class as a general rule should be public, must have a default constructor, must be serializable, and must implement the hashCode () and equals () methods that allows Hibernate test collisions on the primary keys.

Source: link

Although above shows the basics of how to declare two ids in the same template, you can enter the hibernate documentation: link , and although it is in English in item 5.1.2.1 has a good explanation for what you want to do.