select * from t Awhere not exists(select * from t where 课程='A' and 姓名=A.姓名)select * from t where 姓名 not in(select 姓名 from T where 课程='A')
select 姓名 from 表 where 课程 != 'A'
select 姓名 from table_namewhere 课程!='A'