create table tb1(姓名 varchar(10),课程 varchar(10),分数 int); insert into tb1 values('张三','语文',74); insert into tb1 values('张三','数学',83); insert into tb1 values('张三','物理',93); insert into tb1 values('李四','语文',74); insert into tb1 values('李四','数学',84); insert into tb1 values('李四','物理',94) ; select * from tb1; select t.*,100 as "表现" from tb1 t; select *,(select case when 分数>=85 then "优秀" else "666" end as "表现") from tb1 ;