A.插入,更新B.查看,檢索C.查看,存放D.檢索,插入
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;