RE: Counterquestion - is Oracle a He or a She - or an It or

>
>I don't believe Nulls are ambiguous at all. Maybe to you they
>are, but not to me.
>
>They mean nothing. They are the great void. They cannot be
>interpreted to mean anything else. Quite simple really.
>

Yep. Unknown.

>
>For example, in the case of the allergy question. It might be
>appropriate to force the Doctor to select at least one
>response. Maybe "No Known Allergies" or "Did not Reply" is
>the appropriate response. This is why we have a NOT NULL
>constraint. To force something to be entered.

yep.

>
>But in the case of the question "Have you ever been pregnant?"
> For a male, this would be appropriate to be null. It might
>be appropriate for a female also if she did not want to answer
>the question.

Assuming human males, I quite disagree. 'Unknown' is not the correct business answer in this example. 'No' or 'Not Applicable' would be correct. The answer to that question is definitely not unknown.

Now, we'll both probably leave it blank (i.e., null) because the cost and annoyance of being fancier isn't worth it, but that's a technical implementation decision.

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