I have doing the very first example: Person and Event
It defines the one-to-many relationship. One person is assigned many events.

My problem is that i m not abled to store event for a person. But i can retrieve details.
xml goes like this:
<class name="com.dynpro.bean.Person" table="PERSON" lazy="false">
<id name="id" column="PERSON_ID" type="long">
<generator class="native" />
</id>
<property name="age" />
<property name="firstname" />
<property name="lastname" />
<set name="events" table="EVENT">
<key column="PERSON_ID" />
<many-to-many column="id" class="com.dynpro.bean.Event" />
</set>
</class>

Tables are:
Person table:person_id,age,firstname,lastname
Event: id,title,date

This is similar hibernate reference's first example
Please anyone help with this

Advanced Thanks,
Jyeshta

If you do "person.addEvent(event);" or do "person.setEvents(eventsSet);" and then save the person instance without saving the event first, you have to have cascade="save-update" or something on your event set in the hibernate mapping file.

Otherwise, if you don't specify cascading, you have to do something like following:

hi don thanks for your reply.

hmm well.. i got the concept but i struck out with another problem.
Now it s giving the error: Duplicate entry '1' for key 1


Altered mapping file is:
<set name="events" table="EVENT" cascade="save-update">
<key column="personid" />
<many-to-many column="id" class="com.dynpro.bean.Event" />
</set>
key column is field specified is 'personid' in 'event' table which refers 'person_id' of person table.
'id' is PK for event table.
And i have specified :<property name="personid" column="personid" /> in event.hbm.xml.

I am confused here: i wanted to make sure which field u will specify in key column and what field to specify in many-to-many

I used to have that error a lot, but now it's about 3 years ago I was able to use Hibernate in a real project (pfff, EJB2)
I'll check it out when I have time :-)

ok..can i have example programs if u have it as a back up.and could u send me pdfs other than hibernate reference?? or any other stuff that could help me to learn???Here(bangalore) Hibernate wrox is not available

Thanks,
Jyeshta

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