ActiveRecord::Base.pluck_each function 

`ActiveRecord::Base.pluck_each` and `ActiveRecord::Relation#pluck_each` act as combination of `pluck` and `each_row`.
You can request for many attributes and associations attributes like this:
```ruby
Model.pluck_each(:id, :name, child: [:id, :name, { nested_child: :address }]) do |row| 
  # do something here
end
```