A.可變精度浮點值 B.整數(shù)值 C.雙精度浮點值 D.單精度浮點值
A.SELECT SUM(ID)FROM EMP GROUP BY DEPTNO; B.SELECT SUM(ID)FROM EMP ORDER BY DEPTNO; C.SELECT COUNT(ID)FROM EMP ORDER BY DEPTNO; D.SELECT COUNT(ID)FROM EMP GROUP BY DEPTNO;
例如數(shù)據(jù)庫中有A表,包括學生,學科,成績三個字段,數(shù)據(jù)庫結構為 學生學科成績 張三語文60 張三數(shù)學100 李四語文70 李四數(shù)學80 李四英語80 如何統(tǒng)計最高分>80的學科()
A.SELECTMAX(成績)FROM A GROUPBY學科HAVING MAX(成績)>80; B.SELECT學科FROM A GROUPBY學科HAVING成績>80; C.SELECT學科FROM A GROUPBY學科HAVING MAX(成績)>80; D.SELECT學科FROM A GROUPBY學科WHERE MAX(成績)>80;