[rails] reset primary key index

$ rails c
>> Food.delete_all
>> ActiveRecord::Base.connection.execute("DELETE from sqlite_sequence where name = 'foods'")

도움 받은 곳 :

http://stackoverflow.com/questions/1921074/how-to-reset-a-single-table-in-rails

http://stackoverflow.com/questions/1601697/sqlite-reset-primary-key-field