How to fix the Hibernate “object references an unsaved transient instance - save the transient instance before flushing” error

Question

I receive following error when I save the object using Hibernate

object references an unsaved transient instance - save the transient instance before flushi         


        

Answer 1

To add my 2 cents, I got this same issue when I m accidentally sending null as the ID. Below code depicts my scenario (and OP didn't mention any specific scenario).

Employee emp = new Employee();
emp.setDept(new Dept(deptId)); // --> when deptId PKID is null, same error will be thrown
// calls to other setters...
em.persist(emp);

Here I m setting the existing department id to a new employee instance without actually getting the department entity first, as I don't want to another select query to fire.

In some scenarios, deptId PKID is coming as null from calling method and I m getting the same error.

So, watch for null values for PK ID