一道sql试题——据说是盛大的

表结构：id   name   subject   score   createdate

建表语句：

Code
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Score](
    [id] [bigint] IDENTITY(1,1) NOT NULL,
    [name] [nvarchar](50) CONSTRAINT [DF_Score_name]  DEFAULT (''),
    [subject] [nvarchar](50) CONSTRAINT [DF_Score_subject]  DEFAULT (''),
    [score] [float] NOT NULL CONSTRAINT [DF_Score_score]  DEFAULT ((0)),
    [createdate] [datetime] NOT NULL
) ON [PRIMARY]

向表预赛几条数据：

Code
insert into Score
select '1','Ivan.Mao','English','40','2/25/2009 8:13:42.000'
union
select '2','name8','English','80','2/25/2009 8:13:42.000'
union
select '3','Ivan.Mao','Math','80','2/22/2009 8:13:42.000'
union
select '4','Ivan.Mao','YuWen','58','2/22/2009 12:00:00.000'
union
select '5','name8','Math','80','2/21/2009 11:59:59.000'
union
select '7','Ivan.Mao','DiLi','33','2/21/2009 11:59:59.000'
union
select '8','name1','subject1','80','2/21/2009 11:59:59.000'
union
select '9','name2','subject1','80','2/21/2009 11:59:59.000'
union
select '10','name3','subject1','80','2/21/2009 11:59:59.000'
union
select '11','name4','subject1','90','2/21/2009 11:59:59.000'
union
select '12','name5','subject1','100','2/21/2009 11:59:59.000'
union
select '13','name6','subject1','50','2/21/2009 11:59:59.000'
union
select '14','name7','subject1','95','2/21/2009 11:59:59.000'

 

1. 创建时间为3天前0点创建的纪录，20分钟前创建的纪录?

select   *   from  Score
where   DATEDIFF (d,createdate, GETDATE ()) > 3

select   *   from  Score
where   DATEDIFF (n,createdate, GETDATE ()) > 20

 

2. 3门以上不及格学生的学生姓名?

select   [ name ]   from  Score
where  score < 60
group   by   [ name ]
having   COUNT ( * ) >= 3

3.       id   name
          1     a
          2     b
          3     a
          4     a   
     id为identity,只留一条a与一条b

-- select * into Score_Test3 from Score
select   *   from  Score

select   *   from  Score_Test3

delete   from  Score_Test3
where  id  not   in
(
     select   max (id)  from  Score_Test3  group   by   [ name ]  
)

 

4. 总分排名5-7的学生姓名(name,score),最好写成存储过程,请注意并列排名的问题

-- select * into Score_Test4 from Score
select   *   from  Score
select   *   from  Score_Test4

select   top   3  t2. *   
from  
( select   top   7   [ name ] , sum (score)  as  totalScore  from  Score_Test4  group   by   [ name ]   order   by   sum (score)) t2 
order   by  t2.totalScore

 

没有考虑并列排名问题，还待斟酌。。。