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Re: histogram

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David Johnston wrote:
Given that you are actively implementing the code that uses the 1 and 2 I
don't see how it is that egregious.  When generating calculated fields it is
cleaner than the alternative:

Select trunc(distance * 10.)/10., count(*)
From doc_ads
Group by (trunc(distance * 10.))
Order by (trunc(distance * 10.))

It would be nice if you could do:

Select trunc(distance * 10.)/10. AS bin, count(*) AS frequency
From doc_ads
Group by bin
Order by bin

But I do not believe that is allowed (though I may have my syntax wrong...)

David J.

re: 1 and 2. They're horrible (imho) reference to the attributes of the
returned tuple. Or at best an exposure of the implementation. :)

Joel Reymont wrote:
I think this should do what I want

	select trunc(distance * 10.)/10., count(*)
	from doc_ads
	group by 1 order by 1

  Thanks, Joel

I think we're supposed to bottom-post here.

I agree in the case of generated columns and old servers but you see the practice more commonly than really necessary. But in 8.4 at least

select trunc(distance * 10.0 )/10.0 as histo, count(*) as tally
from d group by histo order by tally;


works just fine for me

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