create table testtable(
[id] [int] identity(1,1) not null,
[username] [nvarchar](50) null,
[subject] [nvarchar](50) null,
[source] [numeric](18, 0) null
) on [primary]
go
insert into testtable ([username],[subject],[source])
select n'张三',n'语文',60 union all
select n'李四',n'数学',70 union all
select n'王五',n'英语',80 union all
select n'王五',n'数学',75 union all
select n'王五',n'语文',57 union all
select n'李四',n'语文',80 union all
select n'张三',n'英语',100
go