I am building a geojson with gdal and the ogr tool. I am doing something like to retrieve places of one particular country.
ogr2ogr -f GeoJSON -where "adm0_a3 = 'CODEISO3OFMYCOUNTRY'" places.json ne_10m_populated_places.shp
Then I am drawing all of them using d3. The point is that I want to get only official cities, instead of any other kind of small cities or village or anything else.
Can anyone explain to me how I can achieve that- I mean querying it just to retrieve official cities in these places?
Thanks in advance