Rails 4: dynamic table name possible in `where` on` has_many: through`?

I have an association:

has_many :regions_deployed, -> { where(taggings: { scope: 'deployed' }) },
:through => :taggings, :source => :choice_filter, :source_type => "Region"

      

        
        
        
      

    

This usually works except when used in a joins

named scope clause that is bound to other named scopes that are also bound to taggings

. Postgres then aliases the table name taggings

, but where(taggings: { scope: 'deployed' }

does not reflect that alias. How to specify dynamic table name inside where

?

I think this question is closely related, but it can't get it: Including the same table twice with conditions