dhis2-devs team mailing list archive

[Knut Staring <knutst@xxxxxxxxx>]

Much simplified PHP that works with the db representation below.

On Thu, May 20, 2010 at 1:26 PM, Knut Staring <knutst@xxxxxxxxx> wrote:
> Working on converting all our data to geojson, I've changed my mind
> for representation in the database somewhat. Instead of just having
> the coordinates in one field and the type of geometry in another, it
> will be both more efficient and easier to have just store the full
> geometry string in one field, like this:
>
> {"type": "Point", "coordinates": [6.18218, 45.5949]}
>
> Similarly for Polygon and Multipolygon.
>
> The problem we are encountering is that even with datatype text (in
> Postgresql), the multipolygon strings sometimes are too long for the
> field - not sure why that happens since text is defined as unlimited?
> Our solution has been to both generalize (simplify) and limit
> coordinates to two decimals, but it is still somewhat problematic
> (these gemetries come from the PostGIS geometry format which works
> well)
>
> You can see how the above JSON snippet fits into the fully generated
> GeoJSON file below:
>
> {"type": "FeatureCollection", "features": [{"geometry":
> {"type": "Point", "coordinates": [6.18218, 45.5949]}, "type":
> "Feature", "properties": {"name": "Col d'Arclusaz"}, "id": 472},
> {"geometry": {"type": "Point", "coordinates": [6.27827, 45.6769]},
> "type": "Feature", "properties": {"name": "Pointe de C\u00f4te
> Favre"}, "id": 458}
>
> On Thu, May 20, 2010 at 9:13 AM, Knut Staring <knutst@xxxxxxxxx> wrote:
>> Hi,
>>
>> Please find attached some PHP code I used to connect to a Mysql
>> version of the DHIS2 db and produce GeoJSON.
>>
>> Would be great if we could have a service in DHIS 2 produce the same.
>> Especially because this would allow us to easily create maps (map
>> views) for just one district or province, and not the whole country,
>> as many local users would want (though we may need some more machinery
>> for the display of overlays in that case). This means that. a map view
>> should be attached to an orgunit.
>>
>> Knut
>>
>
>
>
> --
> Cheers,
> Knut Staring
>



-- 
Cheers,
Knut Staring

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