Hi

I'm new to Hibernate so sorry if this is a really basic question, but I'm having trouble finding the answer in the docs.

I have two existing tables A, and B. Table A has a column called 'b_id' which is a foreign key to the primary key of B.

My Java value object for A has a member variable called 'bId'

I'm converting a system from SpringJDBC to Hibernate, but all the mapping examples I come across require A to have an instance of B, which means I have to change my Java code.

I don't mind doing that if I have to, but I was wondering if I can just map 'bId' as a property of A, and somehow mark it as a foreign key in the mapping.

If someone could show me an example of this basic mapping example, I'd be really grateful. I think my head is still in 'relational-mode' which is why I'm having trouble with it...

Regards

Richard

You can just map the "B_ID" column as a property in the A mapping, without worrying about the relationship, so you have not to change your java code.

Just put something like that in A mapping file:


Then you can use theta-style joins in your HQL queries to retreive the relationship value:

Or just use get:


You should however really think about converting the "bId" column in a "b" property of type B. Having an "A" object you can just do:

and you'll get the "b" object without any query.

Thanks Kirby

I will change the Java on your recommendation. The system I'm converting is quite large, so I want to get everything clear in my head so I know I'm doing things right.

Thanks for the clear explanation - really appreciate it.

Richard