Can I make Hibernate replace an object based off a unique column constraint?
hibernate, replace, save, unique-constraint
Solution
I think you're correct, but the closest thing that matches what you're trying to do is documented here - Can Hibernate work with MySQL's "ON DUPLICATE KEY UPDATE" syntax?
Depending on what it is you are trying to do, I would get concerned that you'd be happy to overwrite an existing record if one with the same key/constraint already exists.
I would prefer to remove the unique constraint altogether and grab the one with largest Id for that orderId instead. That way you can at least keep a backup copy of all the contracts with that orderId. This is obviously less efficient on memory space however.
Problem
I'm using Hibernate 4.0.1.Final. I have a table with a unique constraint column … ``` @Entity @Table(name = "cb_contract", uniqueConstraints = {@UniqueConstraint(columnNames={"ORDER_ID"})} ) public class Contract { ... @Column(name = "ORDER_ID") private String orderId; ``` Currently, if I try and save two objects that have the same value for the order ID column, using the below method ... ``` protected void saveOrUpdate(Object obj) { final Session session = sessionFactory.getCurrentSession(); session.saveOrUpdate(obj); } ``` I get a "org.hibernate.exception.ConstraintViolationException: integrity constraint violation: unique constraint or index violation" exception when saving the second instance. Is there a way I can make Hibernate save or replace objects based off the unique column or do I need to search for the object first, delete it if it is there, and then re-insert the one?