1、查询每个学生的各科成绩sql语句:select a.studentid,a.name,a.sex,v1.score as '语文',v2.score as '数学', v3.score as '英语',v4.score as ‘哲学’, (v1.score+v2.score+v3.score+v4.score)/4 as ‘平均成绩’ from Stuednt aleft join (select studentid,score from SQL语句如下:se...