"amy cheng" wrote:
>Oliver, or/and, Gary, and all other experts,
>
>I studied this design:
>1) inheritance and trigger: since "person" and "person-address" relationship
>
>already has triggers, why "organization" and "individual" still need
>triggers with "person-address"?
I don't think that triggers can be inherited automatically. That is why I
did it that way. The implementation of inheritance still needs a lot of
work in PostgreSQL.
>2) "person-address" is the relationship between "address" and
> "person", why "person" still need to DIRECTLY relate with "address"?
> and, again (similar to question 1) why "organization" and "individual"
>still need?
The refint trigger is to make sure that the address record exists before
the person record is updated; if the relation is new there will not be
anything in person_address yet.
The duplication in organisation and individual is again because
inheritance is not fully and consistently implemented.
>Perhaps those codes are just jokes? ????????????????????
The project is not yet complete, so there may be bugs in it!
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Oliver Elphick Oliver.Elphick@lfix.co.uk
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