Re: Best database model for canvassing (and analysing) opinion

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От John R Pierce
Тема Re: Best database model for canvassing (and analysing) opinion
Дата
Msg-id 4A8A9D94.6070004@hogranch.com
обсуждение исходный текст
Ответ на Re: Best database model for canvassing (and analysing) opinion  (Sam Mason <sam@samason.me.uk>)
Ответы Re: Best database model for canvassing (and analysing) opinion
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Sam Mason wrote:
>   SELECT course, date, COUNT(*)
>   FROM application_preferred_date
>   GROUP BY course, date;
>
> Hope that gives you some ideas!
>

the problem as stated is more complex than that.  A student could, in
theory, pick several different courses on the same dates on the
assumption that he doesn't care what course on which date.   so if the
optimizer/solver has counted this student for course1 on date1, he can't
be counted for course2 on that same date, only on an alternate date he
may have also specified.



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