Re: Another generalization hierarchy problem

2005-07-07 Thread abrea
Thanks to all for you help and time. After reading to replies, I think that perhaps a clean way of dealing with individual and company customers in a single table could be to leave them out of the "parties" tree altogether and relate them to the "parties" table without a generalization hierarchy

Re: Another generalization hierarchy problem

2005-07-07 Thread abrea
Thanks to all for you help and time. After reading to replies, I think that perhaps a clean way of dealing with individual and company customers in a single table could be to leave them out of the "parties" tree altogether and relate them to the "parties" table without a generalization hierarchy

Re: Another generalization hierarchy problem

2005-07-07 Thread abrea
Dear Shawn, Thanks for your reply. I find that "individuals" and "companies" each have attributes that are completely irrelevant to the other. E.g. "individuals" have sex and language (so e-mail can be sent to them as "Dear Sir" or "Dear Madam" in both English and Spanish). The only time they ha

Re: Another generalization hierarchy problem

2005-07-07 Thread abrea
Dear Shawn, Thanks for your reply. I find that "individuals" and "companies" each have attributes that are completely irrelevant to the other. E.g. "individuals" have sex and language (so e-mail can be sent to them as "Dear Sir" or "Dear Madam" in both English and Spanish). The only time they ha

Another generalization hierarchy problem

2005-07-07 Thread abrea
Dear list: I am preparing an entity relationship diagram and encountered the following problem: The entity "individual" has the attributes firstname, lastname. The entity "company" has the attributes name, companytype. Now I wish to include the subtype "customer" with the attributes taxid, billin