Hi,
Is it possible to have a mapping for a table with no primary key but just a foreign key. In my case, I have a Parent table and a Child table. The child tables has a foreign key to the parent table.

Parent:
ID - PK
Name - char

Child:
PARENT_ID - FK
Name - char
Value - char

Can someone tell me if it is possible to build a mapping for this kind of relationship?

Thanks,
Javid
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Database Relations depend on Primary Keys and Foreign keys. It isn't necessary that the PK for the child table be used for anything except differentiating one record from the next (as you could easily extract children according to who their parents were), but you need a PK. That's just database design.

technically i agree with gortok. that data model for the child table insinuates that child is a subclass of parent. in geneology that could indeed be true as a child has children and their children have children, etc. in your app, it may or may not be true.

if you cannot change your data model, then you might be able to change your domain model and model that parent/child relationship as a subclass or even by using the composite pattern (i don't know what the parent/child objects really are). i saw an example of the composite pattern a while ago in the hibernate documentation:

http://www.hibernate.org/86.html

if you chose to subclass child of parent then the mapping becomes straightforward with parent and child sharing the same identifier.

hth,

-devon

Thank you all for your response. Since, we are almost nearing deployment I just added an identity column to the table and got it to work.

Thanks again,
Javid