学习目标：

sql

学习内容：

41.查询没有学全所有课程的同学的信息

select *from students where students.stunm not in (select score.stunm from score group by score.stunm having count(score.counm)= (select count(counm) from course))

42.查询至少有一门课与学号为" 1001 "的同学所学相同的同学的信息

select * from students left join score on students.stunm=score.stunm where students.counm in (Select score.counm from score where score.stunm=‘1001’);

select * from students left join score on students.stunm=score.stunm where score.counm in (Select score.counm from score where score.stunm=‘1001’);

Select distinct students.* from students left join score on students.stunm=score.stunm where counm in (select counm from score where score.stunm =‘1001’)

Select distinct s.* from students s left join score sc on s.stunm=sc.stunm where counm in (select counm from score where stunm=‘1001’) and s.stunm != ‘1001’

学习时间：

1月-3月，每天一小时左右

学习产出：

一周一发