-- @param {Float} $1:lat
-- @param {Float} $2:lng
-- @param {Float} $3:radiusKm
SELECT
  d.id, d.name, d.operator, d.capacity_mw,
  ST_AsGeoJSON(d.location)::TEXT as location_geojson,
  ST_Distance(d.location, ST_MakePoint($2, $1)::geography) / 1000 as distance_km
FROM datacenters d
WHERE ST_DWithin(d.location, ST_MakePoint($2, $1)::geography, $3 * 1000)
ORDER BY distance_km