Thank you, this was really helpful!
2013/9/2 Mike Toews <[email protected]> > On 2 September 2013 18:10, Alexander Ulanov <[email protected]> wrote: > > Does this mean that all bounding box queries have to be written with > casting > > to geometry type? Bounding box originates from the browser with google > maps. > > I suppose so, as long as the map used to base the BBOX queries share > the same grid orientation as a lat/long grid (not the case for UTM, > LCC and others, but true for Mercator projections). To get a good idea > of a straight line for the geography type you have to see it on a > globe (or something like Google Earth), but never on a flat map. > > > Related question. Do I really need geography type for my locations if my > > queries are only bounding box and st_dwithin ? > > Geography types are still really handy for ST_DWithin, since they use > nice linear metric units for distances. So I guess it depends how much > you use this function or other distance-based functions. There are > also several ways to get metric area and distance values from geometry > data of long/lat too. Be sure to read the relevant manual section [1] > to help you decide. > > [1] > http://postgis.net/docs/using_postgis_dbmanagement.html#PostGIS_Geography > > -Mike > _______________________________________________ > postgis-users mailing list > [email protected] > http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users >
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