查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩 --解法一: selectt2.s_id, t2.s_name,count(t1.c_id)assun_course,sum(t1.s_score)assum_scorefromstudent t2leftjoinscore t1ont1.s_id=t2.s_idgroupbyt1.s_id --参考解法: selecta.s_id, a.s_name,count(b.c_id)assum_course...
查询所有同学的学⽣编号、学⽣姓名、选课总数、所有课程的总成绩 --解法⼀：select t2.s_id,t2.s_name,count(t1.c_id) as sun_course,sum(t1.s_score) as sum_score from student t2 left join score t1 on t1.s_id = t2.s_id group by t1.s_id --参考解法：select a.s_id,a.s_...