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If I have this entity:
@Entity class Pet { @Id long id; public enum State { ALIVE, DEAD } @Enumerated(EnumType.STRING) @... State state; @... String name; } Can I create a mapping like this:
@Entity class Owner { @OneToMany(condition="state = ALIVE") // or something like that Set<Pet> alivePets; @OneToMany(condition="state = DEAD") Set<Pet> deadPets; } 
831
You can have multiple one-to-many associations, as long as only one is EAGER.
Create an entity class Student. java under com. javatpoint. mapping package that contains student id (s_id), student name (s_name) with @OneToMany annotation that contains Library class object of List type.
Many-To-One relation between entities: Where one entity (column or set of columns) is/are referenced with another entity (column or set of columns) which contain unique values. In relational databases these relations are applicable by using foreign key/primary key between tables.
You can ensure that there are no duplicates by using a Set implementation like HashSet instead of using other data-structure. And instead of adding Job to a customer, create an final inner class in Job class that has private constructor. That ensure that the wrapper inner class can only be created by a job object.
As far as I know this is not part of the JPA spec. At least Hibernates JPA implementation provides an own annotation @Where which can be used:
@OneToMany @Where(clause = "state = 'ALIVE'") Set<Pet> alivePets If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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