在SQL Server数据库中表信息会用到Identity关键字来设置自增列。但是当有数据被删除的话,自增列就不连续了。如果想查询出这个表的信息,并添加一列连续自增的ID,可用如下查询语句:
select Row_Number() over ( order by getdate() ) as init , * from 表名
update need_needData set needtype = '02015004'
from
(
select b.StudentId,a.Id,a.init from
(select Row_Number() over ( order by getdate() ) as init,StudentId,Id from need_needData) a left join
(select Row_Number() over ( order by getdate() ) as init,StudentId,Id from StudentInfo) b on a.init = b.init
) a
where need_needData.Id = a.Id and init%5 = 0