nhibernate - problem with multiple references foreign key -


i have 4 tables :

1 - tbl_cars 

id (pk) car_name model year

2 - tbl_carowner 

id (pk) carid (fk - reference tbl_cars) ownerid (fk - reference tbl_ownerpersnoal or tbl_ownercompany or tbl_ownergov)  ownertype (to make differentiation owner)

3 - tbl_ownerpersonal 

id (pk) name ic_no address

4 - tbl_ownercompany

id (pk) registration_no business_type name address fax mail

5 - tbl_ownergov 

id (pk) agency_name

as can see, need make differentiation between owner because of different field.

how can relate table mysql , nhibernate?

you cannot - it's against basic principles of relational database design. foreign key can ever reference 1 , 1 table - cannot have foreign key references 1 of 3 tables...

what need have 3 fk keys in tbl_carowner

owneridpersonal  (fk tbl_ownerpersonal) owneridcompany   (fk tbl_ownercompany) owneridgov       (fk tbl_ownergov)

and preferably make sure 1 of keys if valid (not null) @ given time.


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