lib/geokit-rails/adapters/sqlserver.rb
module Geokit
module Adapters
class SQLServer < Abstract
class << self
def load(klass)
klass.transaction do
klass.connection.execute <<-EOS
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[geokit_least]') and xtype in (N'FN', N'IF', N'TF'))
drop function [dbo].[geokit_least]
EOS
klass.connection.execute <<-EOS
CREATE FUNCTION [dbo].geokit_least (@value1 float,@value2 float) RETURNS float AS BEGIN
return (SELECT CASE WHEN @value1 < @value2 THEN @value1 ELSE @value2 END) END
EOS
end
self.loaded = true
end
end
def initialize(*args)
super(*args)
end
def sphere_distance_sql(lat, lng, multiplier)
%|
(ACOS([dbo].geokit_least(1,COS(#{lat})*COS(#{lng})*COS(RADIANS(#{qualified_lat_column_name}))*COS(RADIANS(#{qualified_lng_column_name}))+
COS(#{lat})*SIN(#{lng})*COS(RADIANS(#{qualified_lat_column_name}))*SIN(RADIANS(#{qualified_lng_column_name}))+
SIN(#{lat})*SIN(RADIANS(#{qualified_lat_column_name}))))*#{multiplier})
|
end
def flat_distance_sql(origin, lat_degree_units, lng_degree_units)
%|
SQRT(POWER(#{lat_degree_units}*(#{origin.lat}-#{qualified_lat_column_name}),2)+
POWER(#{lng_degree_units}*(#{origin.lng}-#{qualified_lng_column_name}),2))
|
end
end
end
end