IDW-interpolated density per hex grid cell (all cells, including empty ones). Power=2, search radius: res7=15km, res8=8km, res9=4km. Self-density priority: populated cells retain original density. 8 metrics: housing, commercial, industrial, development, institutional, recreational, utility, cadastral. Resolutions: 7 (~5km2), 8 (~0.7km2), 9 (~0.1km2). REFRESH: REFRESH MATERIALIZED VIEW CONCURRENTLY sgkv.mv_hex_density_idw;
area_km2 cadastral_count cadastral_idw commercial_count commercial_idw development_count development_idw hex_id housing_count housing_idw industrial_count industrial_idw institutional_count institutional_idw recreational_count recreational_idw resolution utility_count utility_idw