:select with find_in_batches

How can I include a :select clause with find_in_batches. The following throws an error " Mysql::Error: Unknown column 'users.id' in 'field list': .

    Post.find_in_batches(:batch_size => 100, :select => "users.id, users.name, categories.name, posts.id", :include => [:user, :category]) do |group|     #stuff with group     end

How can I include a :select clause with find_in_batches. The following throws an error " Mysql::Error: Unknown column 'users.id' in 'field list': .

If you want joins use :joins rather than :include

Fred