instruction: Are there classes on Friday for when Prof. Leon Gmeindl teaches 829 ?
response: SELECT COUNT(*) = 0 FROM course INNER JOIN course_offering ON course.course_id = course_offering.course_id INNER JOIN offering_instructor ON offering_instructor.offering_id = course_offering.offering_id INNER JOIN instructor ON offering_instructor.instructor_id = instructor.instructor_id WHERE course.number = 829 AND course_offering.friday = 'N' AND instructor.name LIKE '%Leon Gmeindl%'