"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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