A question that has been bugging me. Here is an example...

I have two tables (Mysql v5.1):

TABLE1: client
FIELD: case_id; int(11), Primary Key, Not Null
FIELD: client_name; varchar(255)

TABLE2: clientlog
FIELD: clientlog_id; int(11), Primary Key, Not Null, Auto Increment
FIELD: case_id; int(11)
KEY `client_index` (`case_id`), CONSTRAINT `clientlog_ibfk_1` FOREIGN KEY (`case_id`) REFERENCES `client` (`case_id`) ON DELETE CASCADE

So a client can have more than one log entry (oneToMany). I am using hibernate annotations to map all this in a very simple example.

It seems that Hibernate Annotations does not have an equivalent to generator class "assigned". The field "case_id" is not generated it is given. Instead I used:


So if I try to do something like:



I get exceptions regarding Client being detached. Which makes sense as I am short-circuiting hibernate.

Does this mean I have to create a new primary key in the Client table just for hibernate? Or is there something else I could do? Interestingly if I use XML mapping (no annotations, using sessions) which gives me the generator class "assigned" it works just fine. It seems to be a limitation of hibernate annotations. Of course, it may have been coded that way for a reason.

Any thoughts on how to approach this would be great. At this point changing the database schema, or the code is a possibility. Just want to make sure I choose the best path.

Thank you.

What happens if the IDs are generated outside of the application. For example - a third party application. In this case the IDs are assigned not generated.

When using annotations it seems you can not use a generator type of assigned. But if you use hibernate XML files and sessions then it works. Maybe I am missing something (would not be the first time). But any information would be great.

Thank you.

I figured it out. Do not specify a generator type, simply say it is an @Id.

@Id
private Long t_id;

Then you can use assigned ids.