Re: haversine formula with postgreSQL

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От Scott Bailey
Тема Re: haversine formula with postgreSQL
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Msg-id 4AB400A9.4090107@comcast.net
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Ответ на Re: haversine formula with postgreSQL  (Greg Smith <gsmith@gregsmith.com>)
Ответы Re: haversine formula with postgreSQL  (Merlin Moncure <mmoncure@gmail.com>)
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> And I think that might work for you.  The performance is going to be
> miserable for large stat sets, because it's going to scan the whole
> aaafacilities table every time and recompute every distance, but as an
> example goes it's probably acceptable.

Something I did when implementing haversine in Oracle was first
calculate a bounding box for lat/lon and only calculate the distance for
cities w/in the bounding box.

Scott

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