sql语句之when then 使用

----sql case when else练习题 ----创建数据表 create table UserLevel ( uId int identity primary key not null, name nvarchar(32) not null, level int default(1) not null ) go insert into UserLevel values(N'犀利哥',1) insert into UserLevel values(N'小月月',2) insert into UserLevel values(N'郭德纲',3) insert into UserL