but no sorting filtering is possible

there is singleton study columns object created in db to reflect current state of the project (single study per smasch instance)

there is singleton study columns object created in db to reflect current state of the project (single study per smasch instance)

address, city, country, data_born, default_written_communication_language, email, first_name, languages, last_name, phone_number, phone_number_2, phone_number_3, postal_code removed from study_subject (all this information is stored in subject)

the code is fixed so unit test passes