I have a project with various parts.... One of which is the calculate the area of all the polygons on a map. When I run the query "select st_area(nycpp.the_geom) from nycpp;" I get a list of all the areas.
Next, I tried adding the results of the query to the nycpp table with UPDATE nycpp SET 开发者_JAVA百科area_sizes = (select st_area(nycpp.the_geom) from nycpp); but get the error -- "more than one row returned by a subquery used as an expression"
I figured out why am I getting the error... what I can not figure out is how write a script that will update all 12K+ records....
Can someone give an example or a link to info on updating multiple records
The database I'm using is PostGIS
Thanks Chris
You are making it to complicated. Try:
UPDATE nycpp set area_sizes=ST_Area(the_geom);
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