text: -- Metrics for basic intersection between LBSN and locations
  SELECT
      t1.id,
      extensions.hll_intersection (hll_union_agg (t1.user_hll), hll_union_agg (t2.user_hll)) AS users,
      extensions.hll_intersection (hll_union_agg (t1.post_hll), hll_union_agg (t2.post_hll)) AS posts,
      extensions.hll_intersection (hll_union_agg (t1.date_hll), hll_union_agg (t2.date_hll)) AS userdays
  FROM
      social.community AS t1,
      spatial.place AS t2
  GROUP BY
      t1.id
  ORDER BY
      posts DESC
  