[GRASSLIST:4070] Re: direction to nearest...?

Eric G. Miller egm2 at jps.net
Fri Jul 12 16:52:47 EDT 2002


On Fri, Jul 12, 2002 at 10:38:59AM +0200, Radim Blazek wrote:

> I wanted suggest also to do that all in database like: select id1,
> first(id2) from (select id1, id2, (x2-x1)^2 + (y2-y1)^2  as d from
> pok1, pok2 where val1 = val2 order by (x2-x1)^2 + (y2-y1)^2) as xxx
> group by id1 ;  etc., but I found that there is no first() aggregate
> function in postgres.

See LIMIT.  Or, maybe a MIN or MAX aggregate?  Or, see builtin postgres
distance operator...

-- 
Eric G. Miller <egm2 at jps.net>



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