Hi - I have the usual order/order items object model i.e. the order object contains a Set of items. However, the underlying database is not broken down into order and orderitem tables, instead there is a single orders table that maps orderDates and products directly i.e.:

1 | 1/1/05 | 1 | 4
2 | 1/1/05 | 2 | 6
3 | 1/1/05 | 3 | 4
4 | 2/1/05 | 1 | 7
5 | 2/1/05 | 2 | 1
...

where the first column is id, the second is orderDate, the third is productId and the fourth is quantity.

How do I go about mapping this to my order/orderItem object model?

Hibernate version: 3.0.5

One way is to have a single class - say OrderAndItem that maps to the table. It can use composite key (orderid, itemid). You can write queries and/or updates that pull up all OrderAndItem for a given orderid, or itemid.

The other is to have views on the db that give the order/orderItem view of the table and map the views to hibernate classes order/orderitem.

Essentially means that you have to do the translation to a normalized form, either at the database level or in java code.

Hope this helps.