sql - 查找第 2 天到最近日期的所有分数

Question

我有一个历史记录表，其中包含每个日期每个组的分数(PK 是组、日期)。可以检索最近第二个日期的所有组的分数的 SQL 查询是什么？

ETA:各组的日期相同(每个组的每个分数同时输入到历史表中)。

Answer 1

select *
from ScoreHistory sc1
where exists
(
    select GroupId, max(ScoreDate) RecentScoreDate
    from ScoreHistory sc2
    where not exists
    (
        select GroupId, max(ScoreDate) RecentScoreDate
        from ScoreHistory sc3
        group by GroupId
        having GroupId = sc2.GroupId and max(ScoreDate) = sc2.ScoreDate
    )
    group by GroupId
    having GroupId = sc1.GroupId and max(ScoreDate) = sc1.ScoreDate
)

设置:

create table ScoreHistory(GroupId int, ScoreDate datetime)

insert ScoreHistory
    select 1, '2011-06-14' union all
    select 1, '2011-06-15' union all
    select 1, '2011-06-16' union all
    select 2, '2011-06-15' union all
    select 2, '2011-06-16' union all
    select 2, '2011-06-17' 

对于 MS SQL 2005 +，查询看起来像下面一样简单

;with cte
as
(
    select *, row_number() over(partition by GroupId order by ScoreDate desc) RowNumber
    from ScoreHistory
)
select *
from cte
where RowNumber = 2