[OSM-talk] get latitude / longitude of points?

[Milo van der Linden]

You might also consider importing with osm2pqsql with the -l flag (use 
lat/lon) that way your database will be in a EPSG:4326 official 
projection (which 900913 is not) and you will have an easier life if you 
want to convert between projections.

I am also a *fan* of using wgs84 in my postgis database when it comes to 
OSM data under the simple rule of fist that it is in my opinion best to 
keep data in the projection it was created with and for GPS this is 
always wgs84. For my national dutch data derived from official 
government bodies; my rule is "store it in EPSG:28992 (the official 
dutch projection) because that is the coordinate-system they survey in.

Andy Allan wrote:
> On Tue, Mar 16, 2010 at 7:19 AM, Torsten Mohr <tmohr at s.netic.de> wrote:
>   
>> Hello,
>>
>> thanks a lot for your hint.
>>
>>     
>>> http://postgis.refractions.net/documentation/manual-svn/ST_X.html
>>> http://postgis.refractions.net/documentation/manual-svn/ST_Y.html
>>>
>>> select st_X(st_transform(way,4326)), st_Y(st_transform(way,4326)) from
>>> planet_osm_point where ...
>>>       
>> I tried it like this:
>>
>> select st_X(st_transform(way,4326)), st_Y(st_transform(way,4326)) from
>> planet_osm_point where name='Berlin' and place='city';
>>
>> But this lead to this error:
>>     
>
> Try transforming via 3395, which always works for me. For reasons I've
> never bothered investigating a direct transform from 900913->4326
> doesn't work, but 900913->3395->4326 does.
>
> e.g. st_X(st_transform(st_transform(way, 3395), 4326))
>
> Cheers,
> Andy
>
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