关于sql语句，实在不知道一下的题目怎么做

来源：百度知道 编辑：UC知道 时间：2024/05/29 19:20:45
1.写出将学生表（student）中的学号字段(num,文本类型)中的数据前两位修改为‘60’、后面的数据不变的语句。
2.写出显示教师表
teacher(tno,tname,tsex,salary,dept)中共有多少个部门和每个部门有多少个教师的语句。其中dept为部门的字段。

select * from Num like '60%'

select dept,部分人数=count(*),
(select count(distinct dept) from teacher) as 部门数
from teacher t
group by dept

update student set num = '60' + right(len(num)-2)

select count(distinct) as dept_num,count(tno) as teacher_num from teacher group by dept

1.
update student set num='60' where sno in(select top 2 sno from student) --sno是学号的列名

2.
select dept,count(tno) from teacher group by dept

1、UPDATE Student SET Num='60'+SUBSTRING(Num,3,LEN(Num))
2、SELECT COUNT(DISTINCT Dept) AS '部门总数' FROM Teacher
SELECT Dept AS '部门',COUNT(tno) AS '教师数量' FROM Teacher
GROUP BY Dept

update student set num = '60' + right(len(num)-2)