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000152_csj@iesd.auc.dk _Tue Jun 8 03:42:25 1993.msg
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Received: from iesd.auc.dk by optima.CS.Arizona.EDU (5.65c/15) via SMTP
id AA05140; Mon, 7 Jun 1993 18:43:50 MST
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(5.65c8/IDA-1.5/MD for <tsql@cs.arizona.edu>); Tue, 8 Jun 1993 03:42:25 +0200
Date: Tue, 8 Jun 1993 03:42:25 +0200
From: "Christian S. Jensen" <csj@iesd.auc.dk>
Message-Id: <199306080142.AA18185@iesd.auc.dk>
To: edrbtsn@cs.indiana.edu, tsql@cs.arizona.edu
Subject: Re: are queries easy to write?
> Ed Robertson writes:
> | Rick Snodgrass says:
> |
> |1. .... Five queries can't be that hard to write.
>
> In fact, for some categories it is difficult to come up with NATURAL
> queries which aren't variations on the same theme. For instance,
> there are few occasions where one is interested only in the time of
> some facts (class O2 - boy this may get me in trouble: "O2 doesn't
> make sense sometimes" :-). The exceptions are very local queries,
> when we already know the fact and just wish its time, or very global
> queries, concerning the overall state ("when were there the most
> employees") which require aggregation or forall.
>
> Anyway, maybe we should have some indication when certain categories
> seem less natural. This would facilitate purning out classes. How
> about a macro like \classremark#1 which Christian can define as he
> pleases, including null.
I agree with Ed's observation that it is not always easy to find five
good queries for a class. (I choose two classes of O2 queries myself!)
I recommend that you feel free to include some general comments for
each or some of the classes you are writing queries for. Simply place
the comments right after the section heading for the class, and before
the first query.
Best regards,
Christian
csj@iesd.auc.dk