I have a model, resource, which has_many categories:
has_many :category_resources, :dependent => :destroy
has_many :categories, :through => :category_resources
I have it setup to filter on categories, for a list view:
records = Resource.includes(:categories).where(“category_resources.category_id” => categories)
This use of includes combined with the condition makes rails use a join to do the include, but, as you’ve found the filtering then filters the included rows, since everything is done with a single query. I’d try something like
Resource.joins(:category_resources).where(“category_resources.category_id” => categories).preload(:categories)
assuming that you want the proloading for performance reasons. This splits out the eager loading stuff from the main query.
Fred
