sql server 从匹配的日期时间中选择最小值

Question

SELECT Id, Value, Sender, Recipient, MIN(DateTime), TypeOf, VideoId, Likes, Comments
FROM xx.dbo.StreamView
WHERE StreamView.TypeOf = 3 AND StreamView.[DateTime] >= "Some DateTime Value Here"

我正在尝试直接获取比给定 DateTime 值更新的最新记录。

执行此查询时，我收到以下错误：

Msg 207, Level 16, State 1, Line 1
Invalid column name 'Some DateTime Value Here'.

另外，当删除此行时AND StreamView.[DateTime] >= "Some DateTime Value Here"

我得到：

消息 8120，第 16 级，状态 1，第 1 行 列 'xx.dbo.StreamView.Id' 在选择列表中无效，因为它不包含在聚合函数或 GROUP BY 子句中。

建议？谢谢。

更新

WITH
  sequenced_records AS
(
  SELECT
    ROW_NUMBER() OVER (ORDER BY [DateTime] DESC) AS sequence_id,
    *
  FROM
    xx.dbo.StreamView
  WHERE
    StreamView.TypeOf = 3
    AND StreamView.[DateTime] >= "2011-12-29 01:38:21.607"
)
SELECT
  *
FROM
  sequenced_records
WHERE
  sequence_id = 1

returns -> Msg 207, Level 16, State 1, Line 11 列名“2011-12-29 01:38:21.607”无效。

更新 2

伙计们，我只需要在一组大于给定日期时间的选定项目中返回一条最短日期时间的单条记录。

Answer 1

如果您要使用 MIN() 之类的聚合函数，则必须使用 GROUP BY 子句对非聚合列进行分组。

见http://msdn.microsoft.com/en-us/library/ms177673.aspx

您还需要将"Some DateTime Value Here" 中的双引号替换为单引号。

试试这个代码：

SELECT 
    Id, 
    Value, 
    Sender, 
    Recipient, 
    MIN([DateTime]), 
    TypeOf, 
    VideoId, 
    Likes, 
    Comments
FROM xx.dbo.StreamView

WHERE StreamView.TypeOf = 3 AND StreamView.[DateTime] >= '1/1/2012'

GROUP BY
    Id, 
    Value, 
    Sender, 
    Recipient, 
    TypeOf, 
    VideoId, 
    Likes, 
    Comments

根据更新的问题：

DECLARE @Date DATETIME = (
    SELECT MIN( [DateTime] ) FROM xx.dbo.StreamView WHERE TypeOf = 3 
        AND [DateTime] >= '1/1/2012' 
);

SELECT TOP 1 * FROM xx.dbo.StreamView WHERE [DateTime] >= @Date;

Answer 2

MIN() 是一个聚合，正如错误所说；您必须使用 GROUP BY 才能使用聚合查询。这意味着您无法获取组的 MIN() 并且同时具有来自组中的一条记录的单个值。

有两种选择...
- 使用 GROUP BY 获取 MIN()，然后使用它来查找匹配的记录。
- 使用替代方法，例如 ROW_NUMBER()

WITH
  sequenced_records AS
(
  SELECT
    ROW_NUMBER() OVER (ORDER BY [DateTime] ASC) AS sequence_id,
    *
  FROM
    xx.dbo.StreamView
  WHERE
    StreamView.TypeOf = 3
    AND StreamView.[DateTime] >= "Some DateTime Value Here"
)
SELECT
  *
FROM
  sequenced_records
WHERE
  sequence_id = 1

注意你需要真正的日期时间，例如'01012012 23:34'

对于没有 ROW_NUMBER() 的环境，您可以使用两个步骤恢复为聚合方法。比如……

SELECT
  *
FROM
  StreamView
WHEREE
  TypeOf = 3
  AND DateTime = (SELECT MIN(DateTime) FROM StreamView WHERE TypeOf = 3 AND DateTime >= '01012012 23:34')

Answer 3

您可以改用子查询：

SELECT Id, Value, Sender, Recipient, DateTime, TypeOf, VideoId, Likes, Comments
FROM xx.dbo.StreamView
WHERE StreamView.TypeOf = 3 
AND StreamView.[DateTime] = (Select MIN(DateTime) from xx.dbo.StreamView where [DateTime] >= 
'Some DateTime Value Here' AND TypeOf = 3)