NoMethodError: undefined method `more_results' for #<Mysql>

I am trying to create rake task to import data from my old php application.But I can not connect to mysql database properly, when I run Old::User.all on rails console ,I get this error :

NoMethodError: undefined method `more_results’ for #

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/connection_adapters/mysql_adapter.rb:623:in `select’

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/database_statements.rb:7:in `select_all'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/query_cache.rb:56:in `select_all'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/base.rb:467:in `find_by_sql'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/relation.rb:64:in `to_a'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/relation/finder_methods.rb:143:in `all'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/base.rb:439:in `__send__'

from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.3/lib/active_record/base.rb:439:in `all'

from (irb):1

Model class Old/user.rb

class Old::User < ActiveRecord::Base

establish_connection “old_database”

Because table name is lowercase

def self.table_name()

"user"

end

end

database.yml

old_database:

adapter: mysql

database: old_database

username: root

password:

socket: /Applications/MAMP/tmp/mysql/mysql.sock