【简答题】分别写出下列各命令或命令组的功能: (1)SELECT DISTINCT 课程名,学分 FROM 课程 WHERE 课程名 LIKE ′%计算机′AND 学分>3 (2)SELECT * FROM 学生 ORDER BY 年龄 (3)SELECT 系名,COUNT(*); FROM 学生,选课; ...
【简答题】Many of us have become so reliant( 依赖的 )on our smartphones that we use them to carry out a staggering( 令人难以相信的 )221 tasks every day. A study of 2, 000 smartphone owners shows that the average user rea...