how to set the relationship between tables in ejb



how to set the relationship between tables in ejb..

Answer / ch.n.v.ganesh

First, relationships are maintained through foreign
keys, but you do not define foreign keys as conventional
EJB variables; they are generated and maintained by the
container.

Second, relationships generate additional methods on the
local interfaces of the EJBs involved. Consequently, you
will need to work with the Home interfaces for beans
through JNDI, rather than using factory classes as you
might for accessing them through their Remote
interfaces.

Finally, Container Managed Relationship (cmr) fields
may be used in EJB QL queries, just like conventional
fields, but only for EJBs within the same jar file.

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