inheritance « Schema « JPA Q&A

1. inheritance and schema creation using JPA annotations

Hi there, In my little project I have a hierarchy of classes: abstract User | |__ Administrator extends User |__ Instructor extends User |__ Student extends User The User class is annotated like so: package scholastic.models; import javax.persistence.*; import; import java.util.*; @Entity @Table(name = "USERS") @Inheritance(strategy = InheritanceType.JOINED) @Embeddable public abstract class User implements Serializable, Comparable { @Id @GeneratedValue(strategy = ...

3. HowTo migrate a schema when changing the inheritance mapping

Hi, will will change the database mapping for the inheritance mapping from "Table per subclass" to "Table per class hierarchy" to increase the database performance. Which is the easiest way to migrate my data from the old database schema to the new schema? Is there any tool support? Thanks for your help Peter Fouquet

4. Problem schema creation because of inheritance