I have two tables one with block group+data and another with geometries of communities. I want to calculate the intersection area so I can later calculate the proportion of each block group in a given community
I wrote this query, which runs successfully but says no rows are affected--they should be. Basically, some block groups fall entirely into a community, and others are bisected by the community boundaries. What is causing this?
SELECT ST_Intersection(bg_pop.geom, com.geom) as new_geom, ST_Area(ST_Intersection(bg_pop.geom, com.geom)) as new_area FROM laco_pop_by_bg as bg_pop, laco_community as com WHERE ST_Intersects(bg_pop.geom, com.geom)