Question

This query is returning the error “ambiguous column name courses.scheduleNumber”. I searched for a solution to the problem, however, a commonly suggested fix was to qualify all of the column names with the table name, which I have already done.

SELECT
  courses.scheduleNumber,
  courses.subject,
  courses.courseNumber,
  courses.sectionNumber,
  courses.credits,
  courses.title,
  courses.room,
  courses.days,
  rooms.building,
  rooms.room,
  courses.startTime,
  courses.endTime,
  courses.instructor
FROM courses
LEFT JOIN courseRooms 
  ON courses.scheduleNumber=courseRooms.scheduleNumber
LEFT JOIN courses 
  ON courseRooms.building=rooms.building AND courseRooms.room=rooms.room;

Answer 1

I think you mean for that final LEFT JOIN courses to be a LEFT JOIN rooms ?