Question

我在sql server 2008数据库中有一个表，其中包含一堆记录和一个日期列。当表的新条目出现时，将自动插入日期。因此，它包含已创建记录的日期。

我正在尝试运行一个查询，该查询会返回此表中最早的日期和最新日期。

我尝试了类似的东西;

SELECT    TOP(1) DateAdded AS firstdate 
FROM      News 
ORDER BY  DateAdded DESC;  

SELECT    TOP(1) DateAdded AS lastdate 
FROM      News 
ORDER BY  DateAdded ASC;

但它只返回'firstdate'。

任何人都可以指导我如何实现这个目标吗？

Answer 1

SELECT 
       MIN(DateAdded) As FirstDate,
       MAX(DateAdded) As LastDate
FROM
       News;

Answer 2

答案是使用聚合。

SELECT
    MIN(DateAdded) AS firstdate,
    MAX(DateAdded) AS lastdate
FROM
    News;

您的查询返回2个结果：每个结果单独工作

Answer 3

您可以使用以下内容：

    select DateAdded     from (SELECT DateAdded,
           row_number() over (order by DateAdded desc) as rn,
           count(*) over () as added_value
    FROM News
) t
where rn = 1
   or rn = added_value
ORDER BY DateAdded DESC

SQL查询将返回表中的最早日期和最新日期

3 个答案: