Table schema:
CREATE TABLE Degree_Programs (degree_program_id VARCHAR); CREATE TABLE Student_Enrolment (semester_id VARCHAR, degree_program_id VARCHAR)

Question: Find the semester when both Master students and Bachelor students got enrolled in.
SQL: SELECT DISTINCT T2.semester_id FROM Degree_Programs AS T1 JOIN Student_Enrolment AS T2 ON T1.degree_program_id = T2.degree_program_id WHERE degree_summary_name = 'Master' INTERSECT SELECT DISTINCT T2.semester_id FROM Degree_Programs AS T1 JOIN Student_Enrolment AS T2 ON T1.degree_program_id = T2.degree_program_id WHERE degree_summary_name = 'Bachelor'