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在PostGIS中按几何分组可以吗？
按几何分组可以吗？ 我们根据多边形的几何形状进行很多计数，这涉及首先将数据相交以对学生实例进行计数。根据学校边界，街区组等： SELECT n.nbhd_id , count(*) AS count_burglaries FROM denver.crime AS c JOIN denver.neighborhoods AS n ON ST_Intersects(c.geom, n.geom) WHERE c.offense_ty LIKE 'BURG%' GROUP BY n.nbhd_id 第二步是包装一个子查询，以便将多边形表中的几何图形重新连接到计数查询中： SELECT count.* , n.nbhd_name , n.geom FROM ( SELECT n.nbhd_id , count(*) AS count_burglaries FROM denver.crime AS c JOIN denver.neighborhoods AS n ON …