[OSM-dev] MySQL GIS extensions - some tipps

[Andreas Kalsch]

Marcus Wolschon schrieb:
> On Thu, Jul 23, 2009 at 8:35 PM, Andreas Kalsch<andreaskalsch at gmx.de> wrote:
>   
>>> How much would that be without filtering? Since I have no clue what
>>> are "relevant tags and relations" for you.
>>>
>>>       
>> Relevant features are features which represent a GeoObject. Nodes which
>> are just part of ways and ways which are just part of multipolygons are
>> not relevant in this context.
>>     
>
> Ah, I see.
> As I need the ways that share a given node and tags on nodes
> in ways are very important I would only store a POINT on the nodes
> but not use any GIS-Extension on the ways. (such as POLYLINE)
>
> Do I loose precision if I store the lat+lon of a node as a POINT
> and convert it back?
>   
You can save them as int or better as float. I use float - you will not 
loose precision and don't have to convert.
> I`m asking because I have an "edit"-button that exports the
> currently visible area and starts the latest JOSM with it
> so co-drivers can fix mistakes in the map right as the driver encounters
> them.
>
> Marcus
>