Question

假设我有一个带有ID标识列的表，一些数据和一个日期戳。像这样：

1   data    5/1/2013 12:30
2   data    5/2/2013 15:32
3   data    5/2/2013 16:45
4   data    5/3/2013 9:32
5   data    5/5/2013 8:21
6   data    5/4/2013 9:36
7   data    5/6/2013 11:42

如何编写一个查询，向我显示一个时间戳为5/4的记录？该表有数百万条记录。我做了一些搜索，但我不知道该怎么称呼我正在寻找的东西。：/

Answer 1

declare @t table(id int, bla char(4), timestamp datetime)
insert @t values
(1,'data','5/1/2013 12:30'),
(2,'data','5/2/2013 15:32'),
(3,'data','5/2/2013 16:45'),
(4,'data','5/3/2013 9:32'),
(5,'data','5/5/2013 8:21'),
(6,'data','5/4/2013 9:36'),
(7,'data','5/6/2013 11:42')

select timestamp
from
(
  select rn1 = row_number() over (order by id), 
  rn2 = row_number() over (order by timestamp), timestamp
  from @t 
) a
where rn1 not in (rn2, rn2-1)

Answer 2

在2008年r2，这将是一种方式

DECLARE @Table AS TABLE
(id INT , ladate DATETIME)

INSERT INTO @Table VALUES (1, '2013-05-01')
INSERT INTO @Table VALUES (2, '2013-05-02')
INSERT INTO @Table VALUES (3, '2013-05-03')
INSERT INTO @Table VALUES (4, '2013-05-05')
INSERT INTO @Table VALUES (5, '2013-05-04')
INSERT INTO @Table VALUES (6, '2013-05-06')
INSERT INTO @Table VALUES (7, '2013-05-07')
INSERT INTO @Table VALUES (8, '2013-05-08')

- 我在排序顺序中添加了记录，但如果不是只是确保在查询中排序

SELECT t2.ladate FROM @Table T1
INNER JOIN @Table T2 ON T1.Id = T2.Id + 1
INNER JOIN @Table t3 ON t2.id = t3.id + 1
WHERE t3.ladate < t2.ladate AND t2.ladate > t1.ladate

- 我假设你的Id都在那里，1,2,3,4,5 ....没有丢失......如果有rownumbers缺失，你可以使用row_number（）

如何找到乱序记录 - SQL？

2 个答案: