An user sent us this, which might be a nice addition for a future JDO release.
An outline of his wish is 1-1 or 1-N associations with properties allowing to
distinguish from other associations to same types. A kind of discriminator at
field level.
Regards,
-------------
I have checked docs looking for examples but with no
success.
Recalling a typical example of a person with 2 addresses,
defined as distinct members of Person class,
I would map the Address class in a table with a FK to Person
and some extra (constant) column as discriminator.
class Person {
String name;
Address home;
Address work;
...
}
Address {
String street;
String city;
..
}
Table PERSON
-----------------
PERSON_ID
NAME
Table ADDRESS
-------------------
ADDRES_ID
STREET
CITY
PERSON_ID
ADDR_TYPE = {"HOME", "WORK"}
ADDR_TYPE values should be transparently managed by
JDO implementation
Is it possible with jpox standard/extensions ?
Is it possible for collections too (i.e. 2 addresses collections) ?
Guido
