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Hibernate version:3.0.3

Mapping documents:

Code between sessionFactory.openSession() and session.close():

Full stack trace of any exception that occurs:

Name and version of the database you are using:Oracle 8i

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:

This is not a request for help debugging, I just don't know what to look for and I was hoping someone here could point me to a section of the manual that addresses my problem. I don't really care to read through the entire manual looking for a piece of functionality that may not even exist.

I am working on a piece of functionality that builds a survey. Each question is a separate object stored in the database and associated to a survey id. Adding new questions is no problem, but removing questions is because I don't know how to tell hibernate that, when I write the object back to the database that it should delete anything not present on the survey. So if I added 3 questions and decided to delete one, I delete it from my object but there is simply nothing done to it in the database when I write it back.

So my object may look something like this:

SurveyX
\-Question1
|-Question2
|-Question3

When I remove question 3 and write it back to the database, it writes:

surveyxid, question1
surveyxid, question2

but since question 3 was already there, when I get the values back, I get:

SurveyX
\-Question1
|-Question2
|-Question3

because it read question 3 because it was already there. Does hibernate have some sort of feature that knows question 3 was on the object and has been removed so it should be removed from the database? If so what is it called and where do I find the reference for how to use it in the manual?

Thanks in advance

i think your actual problem is that you're updating the survey object when you should be explicitly deleting the question object you wish to remove.

but i suggest you have a look at

http://www.hibernate.org/hib_docs/v3/reference/en/html/collections.html
especially section 7.3.2 bidirectional associations

and

http://www.hibernate.org/hib_docs/v3/reference/en/html/example-parentchild.html
for some examples.

You might be looking for the cascade="delete-orphan" attribute (I didn't quite understand your problem)?

See http://www.hibernate.org/hib_docs/v3/reference/en/html_single/#objectstate-transitive

Ok, that was what I was thinking I would have to do. I just didn't want to write something separate if there was a way to do it in Hibernate just through the mapping file.

Thanks.