difference between Home & Component business methods?

[yamini nadella]

what is the difference between Home & Component business methods?.
can we use ejb-ql in HOME business methods?
How EJBHOME business methods differ from home FIND methods?
does bean provider has to write the logic for ejbHome method in bean class?

Yamini.

[Paulus Maessen]

Home methods are used to implement business logic that is not related to a specific entity bean. You can't use EJB-QL for Home methods. You could implement a ejbSelect method on your bean though and call this method from within a Home method.

An ejbSelect method is not required to return references to entities, it may also return the values of a specific (CMP) field for entities satisfying certain criteria.

A Find method is used to obtain (a collection of) *references* to specific entities satisfying certain criteria, which you provide by means of EJB-QL.