2013-12-17 36 views
-1

我有2個表:SQL幫助從空虛的結果中獲得結果,該怎麼辦?

課程(coursecode,名稱,描述,點)

結果(studentnr,coursecode,teachernr,等級,日期)

我努力做到以下幾點:

輸入所有課程的課程代碼和課程名稱, ,其中任何學生都未達到成績。

SELECT DISTINCT course.coursecode, results.coursecode 
FROM course, results 
WHERE results.grade = 0.0 
GROUP BY course.coursecode 
+0

或者換句話說,你正在尋找,看看那裏的''通過分組coursecode'一個'coursecode'的SUM'有(即'HAVING')的值'0'? – nrathaus

回答

0

試試這個

SELECT course.coursecode, SUM(results.coursecode) AS sum_course 
FROM course, results 
WHERE results.coursecode = course.coursecode 
GROUP BY course.coursecode 
HAVING sum_course = 0