X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FCensus.py;h=1b203124916535ae424cc35a1a714dea4de34d27;hb=77929a35679206577cfaeb2d64936b05d3d6ab5b;hp=0f8d23473144d38602e3094797de3f44cd9b05fb;hpb=73a63cfdfdc7ea6db01572d5f76f1e0e7a16e37f;p=dead%2Fcensus-tools.git diff --git a/src/Census.py b/src/Census.py index 0f8d234..1b20312 100644 --- a/src/Census.py +++ b/src/Census.py @@ -36,9 +36,8 @@ class Database: query = """ SELECT population_density - FROM (sf1_blocks INNER JOIN tiger_blocks - ON sf1_blocks.blkidfp00=tiger_blocks.blkidfp00) - WHERE ST_Contains(tiger_blocks.the_geom, + FROM blocks + WHERE ST_Contains(blocks.the_geom, ST_SetSRID(ST_Point(%.6f, %.6f), %d)); """ @@ -61,7 +60,7 @@ class Database: """ cursor = self.connection.cursor() - # We're ready to build our query, one step at a time. Firsy, we store + # We're ready to build our query, one step at a time. First, we store # the Text->Geom conversion in a variable; this just makes the query a # little easier to read. geometric_object = "ST_GeomFromText(%s, %d)" @@ -77,9 +76,9 @@ class Database: # result. # query = """ - SELECT SUM(sf1_blocks.pop100 * - ( ST_Area(ST_Intersection(%s, tiger_blocks.the_geom)) - / ST_Area(tiger_blocks.the_geom) ) + SELECT SUM(pop100 * + ( ST_Area(ST_Intersection(%s, blocks.the_geom)) + / ST_Area(blocks.the_geom) ) ) AS covered_population """ % geometric_object sql_params = (well_known_text, self.srid) @@ -88,15 +87,14 @@ class Database: # Join our two block tables, so that we have both the demographic # and geometric data. query += """ - FROM (sf1_blocks INNER JOIN tiger_blocks - ON sf1_blocks.blkidfp00 = tiger_blocks.blkidfp00) + FROM blocks """ # We only need to calculate the covered population for the blocks # that actually intersect our object. query += """ - WHERE (ST_Intersects(%s, tiger_blocks.the_geom)) + WHERE (ST_Intersects(%s, blocks.the_geom)) """ % geometric_object # geometric_object hasn't been substituted yet, so we need # to add the sql_params twice. @@ -129,9 +127,9 @@ class Database: cursor = self.connection.cursor() query = """ - SELECT ST_AsText(tiger_blocks.the_geom) - FROM tiger_blocks - WHERE tiger_blocks.blkidfp00 = %s; + SELECT ST_AsText(the_geom) + FROM blocks + WHERE blkidfp00 = %s; """ sql_params = (blkidfp00,)