in elasticsearch-model/lib/elasticsearch/model/adapters/multiple.rb [68:80]
def __records_for_klass(klass, ids)
adapter = __adapter_for_klass(klass)
case
when Elasticsearch::Model::Adapter::ActiveRecord.equal?(adapter)
klass.where(klass.primary_key => ids)
when Elasticsearch::Model::Adapter::Mongoid.equal?(adapter)
klass.where(:id.in => ids)
else
klass.find(ids)
end
end