A.可變精度浮點(diǎn)值 B.整數(shù)值 C.雙精度浮點(diǎn)值 D.單精度浮點(diǎn)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(kù)中有A表,包括學(xué)生,學(xué)科,成績(jī)?nèi)齻€(gè)字段,數(shù)據(jù)庫(kù)結(jié)構(gòu)為 學(xué)生學(xué)科成績(jī) 張三語文60 張三數(shù)學(xué)100 李四語文70 李四數(shù)學(xué)80 李四英語80 如何統(tǒng)計(jì)最高分>80的學(xué)科()
A.SELECTMAX(成績(jī))FROM A GROUPBY學(xué)科HAVING MAX(成績(jī))>80; B.SELECT學(xué)科FROM A GROUPBY學(xué)科HAVING成績(jī)>80; C.SELECT學(xué)科FROM A GROUPBY學(xué)科HAVING MAX(成績(jī))>80; D.SELECT學(xué)科FROM A GROUPBY學(xué)科WHERE MAX(成績(jī))>80;