Re: DISTINCT vs. GROUP BY

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От Bruce Momjian
Тема Re: DISTINCT vs. GROUP BY
Дата
Msg-id 200509202245.j8KMj7Z19667@candle.pha.pa.us
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Ответ на Re: DISTINCT vs. GROUP BY  ("Jim C. Nasby" <jnasby@pervasive.com>)
Ответы Re: DISTINCT vs. GROUP BY  ("Jim C. Nasby" <jnasby@pervasive.com>)
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Jim C. Nasby wrote:
> > What do these URL's have that the current TODO does not?
> > 
> > * Consider using hash buckets to do DISTINCT, rather than sorting
> > 
> >   This would be beneficial when there are few distinct values.  This is
> >   already used by GROUP BY.
> 
> Maybe it's just me, but the recent run-through of the TODO list
> indicated that there's a fair number of items that people look at and
> don't really knowh what they mean. Providing the context (ie: email
> thread) that spawned an idea seems extremely valuable in being able to
> explain the idea behind a TODO item. They also usually contain valuable
> tips about how a TODO could be implemented. In this example, having
> quick reference to the discussion about hashagg and first()/last() would
> probably prove useful.

True, but sometimes the thread winds all around and there isn't a
definative explaination of how to go at something.  I woul rather digest
the information to improve it, rather than require people to wade around
in an email thread.  Is there some detail the TODO is missing?

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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