weird_mongoid.rb

#two questions -- why does .count not return the narrowed down result set size, and why does .where seem to alter variable a?

a = Star.where(:brightness => 0)
=> #<Mongoid::Criteria:0xb6af2948 @documents=[], @options={}, @selector={:brightness=>0}, @klass=Star>

a.size
=> 1430

a.count
=> 1430

a.where(:name => /local/).count
=> 1430

a.where(:name => /local/).size
=> 286

a.count
=> 1430

a.size
=> 286