SELECT product_id FROM problems AS T1 JOIN staff AS T2 ON T1.reported_by_staff_id = T2.staff_id WHERE T2.staff_first_name = "Christop" AND T2.staff_last_name = "Berge" INTERSECT SELECT product_id FROM problems AS T1 JOIN staff AS T2 ON T1.closure_authorised_by_staff_id = T2.staff_id WHERE T2.staff_first_name = "Ashley" AND T2.staff_last_name = "Medhurst"
Apa saja ID produk untuk masalah yang dilaporkan oleh Christop Berge dengan penutupan yang disahkan oleh Ashley Medhurst?
CREATE TABLE problems (reported_by_staff_id VARCHAR, closure_authorised_by_staff_id VARCHAR); CREATE TABLE staff (staff_id VARCHAR, staff_first_name VARCHAR, staff_last_name VARCHAR)