Active record save not working

Code :

task :removesign do

ActiveRecord::Base.establish_connection(
:adapter => ‘postgis’,
:database => ‘’,
:username => ‘postgres’,
:password => '
*’,
:host => ‘localhost’)

class Polygon < ActiveRecord::Base
end
Polygon.all.each do |poly|
poly.Cname.gsub!(’-’, ’ ')
puts poly.Cname
poly.save
end
end

Everything works…But when I check the database nothing has
changed???

Tried save and save! to no avail…

Anybody has an idea what went wrong?

Thanks