Hi everyone,
http://postgis.refractions.net/docs/ST_DWithin.html
I see the ST_DWithin function that we can we can determine the geometries
are within a specified distance of one another.
*
ST_DWithin*(*geometry* g1, *geometry *g2, double precision distance_of_srid)
;
*ST_DWithin*(*geography* gg1, *geography *gg2, double precision
distance_meters);
Could you explain me when we use *geometry *and when *geography*.
Geometry which is a geometry tupe: POINT, LINE, POLYGON ... ?
Geography: ...?
...
Cheers.
--
Liem Nguyen
Developer
Axon Active Corp.
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