Re: circular relationships ok?

On 3 Mar 2006 12:50:31 -0800, "Marshall Spight" <marshall.spight_at_gmail.com> wrote:

>Gene Wirchenko wrote:
>> On 2 Mar 2006 18:51:01 -0800, "Marshall Spight"
>> <marshall.spight_at_gmail.com> wrote:
>> >
>> >I'm not getting it. If we're talking about husband and wife in
>> >a context in which there is exactly one-for-one always,
>> >then we are talking about a table of married people. In
>>
>> No. The husband and wife exist as separate entities and may be
>> referred to individually. There may *also* be a table reflecting the
>> marriages.
>>
>> >which case, why wouldn't I have HusbandBirthday, WifeBirthday,
>> >etc.? In fact, I don't really see how the particular domain
>>
>> Because you probably want the birthdate of the person regardless
>> of the role the person has in a marriage. People who are not married
>> have birthdates, too.
>
>This line of reasoning doesn't work for me at all. The question
>was whether to put data items which are exactly-one-to-exactly-one
>in the same table; it is not relevant to argue that you might not
>want to do so because they might not be exactly-one-to-exactly-one.

     If the persons table has information on both married and unmarried persons and there is a table about marriages, where do you think the brithdates should go?

     To me, putting it in the marriages table is ludicrous. An unmarried person has a birthdate.

Sincerely,

Gene Wirchenko Received on Fri Mar 03 2006 - 16:19:04 CST