In one transaction, is it safe to do multiple sessin.save(obj) ? Of course, each time, with a different object.

Thanks...

Of course it is.

Of course :-), but I keep getting the below exceptions. In essence, I do the following:

1. Employee e = new Employee();
2. TreeSet ts = new TreeSet();
3. ts.add(new Office())...blabala ad infinitum.
4. e.setOffices(ts);
5. session.save(e);
6. Obtain an office iterator from e and for each item do a session.save(office);

I use MySQL and autoincrement and "native" id. After 5, I print the id, and indeed, there is a new object id, but then the below happens...


004-04-26 01:07:06,566 ERROR http8080-Processor22 net.sf.hibernate.JDBCException: Could not execute JDBC batch update
at net.sf.hibernate.impl.BatcherImpl.executeBatch(BatcherImpl.java:129)


Caused by: java.sql.BatchUpdateException: Deadlock found when trying to get lock; Try restarting transaction, message from server: "Lock wait timeout exceeded; Try restarting transaction"

For each Office o, I am also doing a o.setEmployee(e)...

And there is no cascade set in the .hbm files.

It's just a simple one-to-many and I can't get it to work..:-(

Employee ---*-> Office

So, Employee --*> Office.

Office holds a foreign key to Employee and in the Office POJO, one can setEmployee(). In the Employee POJO, one can setOffices().

1. Employee e = new Employee();
2. Set tsOffices = new TreeSet();
3. Office o = new Office();
3. tsOffices.add(o);
4. e.setOffices(tsOffices)
5. o.setEmployee(e);

6. session.save(e);
7. session.save(o);

Won't work!!! I keep getting deadlock. HOWEVER, if I don't do step 4, then it works. Can someone explain what I am doing wrong? If I can't do step 5, then Hibernate is a major PITA to use.

This is againsta MySQL. The Employee table has a PK that is auto-incremented. And the Office table has a employeeId which is a foreign key poiting to the Employee table. The Office POJO has no employeeId, only a field to setEmployee().

Thanks...

Do you do proper transaction handling with the hibernate Transaction API or with JTA?

I do. Anyway, the next day, I restarted all the machines, re-run the same code, and it all worked...??!??

I am happy...