#tagged_with method output. The solution would be to use a custom query.[attr]_was, [attr]_chagned?, [attr]_previously_was are some among the helpful methods implemented in ActiveModel::Dirty module.bundle install of a Ruby on Rails project w.r.t. nio4r. The issue generally is the result of implicit function declaration causing errors compiling native C extensions.where.not(...) query method will surely find the query.invert_where query method a welcoming feature. It allows us to easily invert entire queries.servers.