Sql 将数据合并成一行

初始数据示例：

 Project   |   Modified   | LastModify |
 ---------------------------------------
 Project 1 |  12.01.2018  |      3     |
 Project 2 |  10.02.2017  |      2     |
 Project 1 |  15.01.2018  |      2     |
 Project 1 |  18.01.2018  |      1     |
 Project 2 |  15.02.2017  |      1     |

我通过查询得到以下结果：

SELECT *
, Row_number() over (partition by Project order by Modified desc ) as LastModify
FROM Table_A

我需要为column

Lastmodify=1

i、 e.为每个

项目

获取一行，包括第一次修改日期和最后一次修改日期

预期结果如下所示：

 Project   |   Modified   | LastModify | FirstModifyDate|
 ----------------------------------------------------
 Project 1 |  18.01.2018  |      1     |  12.01.2018   |
 Project 2 |  15.02.2017  |      1     |  10.02.2017   |

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如何执行此操作？

如果您的Sql server版本等于或高于2012，这将起作用：

SELECT *
, Row_number() over (partition by Project order by Modified desc ) as LastModify
, First_value(Modified) over (partition by Project order by Modified asc) [FirstModifyDate]
FROM Table_A

---

我已经创建了一个类似于您的数据的表，并应用了可能有用的查询

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sql server版本？2017，抱歉，我没有将版本添加到标记中

SELECT new.project
    ,new.times
    ,new.pdate
    ,sec.p1date
FROM new
INNER JOIN (
    SELECT child.project AS p
        ,child.pdate AS p1date
    FROM new AS child
    INNER JOIN new ON child.project = new.project
    GROUP BY child.project
    HAVING child.times = MAX(child.times)
    ) AS sec ON sec.p = new.project
WHERE new.times = 1