On Tue, Jul 17, 2007 at 01:51:21PM +0100, ann hedley wrote:
> What I want is the average and stddev of the set of lengths returned by
> this query. Something like...
>
> select average(select distinct on (id) length(consensus) from cluster
> order by id,length(consensus) desc);
I think this is what you're looking for:
select avg(length)
from (
select distinct on (id) length(consensus)
from cluster
order by id, length(consensus) desc
) s;
--
Michael Fuhr
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