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代码：create view good_totalasselect gid,sum(quantity) totalfrom sale_recorderwhere sale_date between '2010-04-01' and '2010-07-31'group by gidps:sum()

本题目要求编写SQL语句，利用sh_goods表创建视图view_goods，包含商品打折前后的价格信息。视图中包含四列，分别为商品id，商品名称，商品原价格（old_price）和商品打五折后的价格（new_price）代码：create view view_goodsasselect id,name,price old_price,price*0.5 new_pricefrom sh_goods...

将student表中的数计学院的学生信息插入到stu表中。提示：请使用INSERT语句作答，stu数据表已存在，结构同student一样。代码：insertinto stuselect *from studentwhere dept='数计学院'PS：插入一行：insertinto<表名>values<值>比如：insert into stu('sno','cno','grade')values('01','1','grade')

代码：select sc.cno '课程号',cname '课程名',Max(grade) '最高成绩',min(grade) '最低成绩',avg(grade) '平均成绩'from sc left join cou on sc.cno=cou.cnogroup by sc.cno,cnamehaving count(*)>=2 and min(grade)>=60 and count(*) = count(grade)ps:count(*) = count(grad...

select course.cno,cname,count(sno) totalfrom course left join score on course.cno=score.cnowhere attribute='必修'group by course.cno,cname拓展：1、等值连接、外连接：select *from course,scwhere course.cno=sc.cnoselect*from course left join sc on cour...