In JBoss, by default, you do not need to have a jbosscmp-jdbc.xml. JBoss CMP 2.0 will figure out what DB tables need to be created and mapped to your Entity Bean.

THe final version of this workbook goes into more detail on mapping relationships to tables. Until then, JBoss CMP 2.0 docs are a must (they are a must anyways even with workbook). ITs only $10 and available under the documentation link from www.jboss.org.

> A general comment:
> For me, one of the hardest pieces of the xml puzzle
> for 2.0 is the relationship. I would love to see a
> detailed explanation somewhere for the pieces of the
> xml that participate in describing them. I mean, the
> key-fields element and its key-field subelement are
> mentioned so briefly in the workbook and sometimes
> it's incredibly difficult to figure out what object
> we're referring to when we say the name of the
> atttribute that is the key and what table we're
> referring to when we provide the name of the key
> column. The DTD simply says that this information is
> intrerpreted differently depending on the
> relationship mapping. No other detail is provided
> there. It makes it harder still when the name of the
> attribute is almost always 'id'.
> Also, the fact that you don't have to add
> ejb-relationship elements to the jbosscmp-jdbc.xml
> file to describe relationships in exercise 5.3 is
> completely glossed over. I know someone wrote here
> that they thought the documentation must be wrong. I
> would like to see an explanation as to why you don't
> need to do this. When do I need to and when do I not
> need to?
> I'd be happy to help with any documentation, just let
> me know what I can do.