これは私のOracleクエリです:
SELECT      DISTINCT Student.student_id, student_name, SUM(credit)
FROM        Student, Class, Enrolls
WHERE       Student.student_id = Enrolls.student_id
AND         Class.schedule_num = Enrolls.schedule_num
AND         Class.semester = Enrolls.semester
AND         grade != 'F'
AND         grade IS NOT null
ORDER BY    student_id ASC;
を追加するまで、クエリは正常に機能しましSUM(credit)た。その後、私は得る:
ORA-00937: not a single-group group function
助けてください、ありがとう。