遵循以下几行的查询应该可以帮助您入门：
select s.name , s.weight , ((s.weight/st.avgweight) * 100) as weight_apgaw , ((s.height/st.avgheight) * 100) as weight_apheifrom student s join ( select grp_id , avg(weight) as avgweight , avg(height) as avgheight from student group by grp_id ) st on s.grp_id = st.grp_id
