i want to know the method that modify type value in "table per subclass".

example,

Member class (Parent class)
- tablename : MEMBERS
- type value: "group" (discriminator value)

User Class (Chidren class)
- tablename : MEMBER_USER
- type value : "user" (discriminator value)
- name : "Smith"

Department Class (Childrent Class)
- tablename : MEMBER_DEPARTMENT
- type value: department (discriminator value)
- code : "dep01"

i want to changed type and class (user class -> departemnt class)

next, sample code. but it's incorrect code.



but, our database's type value never changed. how can i solve this problem?

I'm pretty sure that's impossible. What you actually want to do, is change the type of an object, which is impossible in Java. Since Hibernate maps to Java objects, it makes sense that Hibernate disallows it as well.

Consider that you already have a reference to the object, then magically change the type of said object through hibernate... what would happen to your previously fetched (and hence cached) object?

If you really need to do this, you'd have to do the SQL work manually outside of a Hibernate session. But it's more likely that something in your design is flawed - though I could easily be wrong.