CREATE OR REPLACE TABLE `carto-dw-ac-vs5d76ww.shared.madrid_h3_study_area_enriched_15minwalk_tourism_intersection_output` AS
WITH
  areas_cte AS (
    SELECT
      h3,
      enrichment.__carto_intersection AS covered_area,
      ST_AREA(`carto-un`.carto.H3_BOUNDARY(h3)) AS total_area
    FROM `carto-dw-ac-vs5d76ww.shared.madrid_h3_study_area_enriched_15minwalk_tourism_intersection`,
    UNNEST (__carto_enrichment) AS enrichment
  )
SELECT
  h3,
  covered_area AS carto_intersection,
  total_area AS carto_total,
  covered_area / total_area AS covered_percentage,
  CAST(NULL AS BOOLEAN) AS placeholder
FROM areas_cte;