Re: dirty data

mAsterdam wrote:
> Gene Wirchenko wrote:
>

>> mAsterdam wrote:
>>
>>> Gene Wirchenko wrote:
>>>
>>>> mAsterdam wrote:
>>>>
>>>>> Gene Wirchenko wrote:
>>>>>
>>>>>> dawn wrote:
>>>
>>> [snip agreement]
>>>
>>>>>>> There are always differences of opinion about what constitutes a
>>>>>>> student on a campus.  Finance people often use the term as if the
>>>>>>> student were the same as a corporate customer.  Student = 
>>>>>>> Customer.  If
>>>>>>> someone has received some approval to audit a course for zero 
>>>>>>> dollars,
>>>>>>> the instructor might consider them a student.  That is just an 
>>>>>>> example,
>>>>>>> but the point is that entity names are also just words and are
>>>>>>> interpreted by humans, each of whom brings a different context to 
>>>>>>> the
>>>>>>> meaning of the word.
>>>>>>
>>>>>>
>>>>>>    Such a student is a student by the normal use of the term. I 
>>>>>> think this factor is what causes a lot of the trouble.
>>>>>
>>>>>
>>>>> Could you elaborate some on this factor?
>>>>
>>>>
>>>>     One who studies.  If I study medieval history, I am a student.  I
>>>> might not be enrolled anywhere.  I could even be a leading authority
>>>> in the field.
>>>
>>>
>>> I see what you mean, but I am not sure you got my question right.
>>> I meant: what is this factor which is causing a lot of trouble?
>>> In more modern words: what is the anatomy of this anti-pattern?
>>> We might learn to more easily recognize it.
>>
>>
>>      I think that the trouble comes from overloading terms.  "student"
>> already has a meaning.  What distinguishes the special meaning from
>> the more literal meaning?  If I do not know that a special meaning is
>> in use in a specific context, I can make a lot of mistakes.

i may be stepping on nuances that i haven't noticed in this thread, but i think the above is getting close to the truth, at least the truth these days. so far, databases ARE naive and so are their "tests". for example, if a user thinks someone is a student and can "fill in" the values that the db predicates want for a student, then the someone is a student as far as the db is concerned, no matter what anyone else thinks.

pc Received on Fri Aug 12 2005 - 04:28:38 CEST