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));
"""
# 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)
# 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.
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,)