Question

我有2个表： @Temdate1

+------+------------+---------------+--------+
| Year | Entry_Date | DeliveryMonth | Symbol |
+------+------------+---------------+--------+
| 2016 | 2016-01-07 | June          | ABC    |
| 2015 | 2015-01-06 | June          | ABC    |
| 2014 | 2014-01-05 | June          | ABC    |
| 2016 | 2016-03-05 | Sep           | CDE    |
| 2015 | 2015-03-04 | Sep           | CDE    |
| 2014 | 2014-03-03 | Sep           | CDE    |
+------+------------+---------------+--------+

和AllProducts

+-----------------+---------------+--------+
|      Date       | DeliveryMonth | Symbol |
+-----------------+---------------+--------+
| 2016-01-07      | June          | ABC    |
| 2016-01-08      | June          | ABC    |
| 2016-01-09      | June          | ABC    |
| 2016-01-10      | June          | ABC    |
| 2015-01-01      | June          | ABC    |
| 2015-01-02      | June          | ABC    |
| 2015-01-03      | June          | ABC    |
| 2014-01-05      | June          | ABC  |
+-----------------+---------------+--------+

结果我正在寻找更新的表@Temdate1：

+------+------------+---------------+--------+
| Year | Entry_Date | DeliveryMonth | Symbol |
+------+------------+---------------+--------+
| 2016 | 2016-01-07 | June          | ABC    |
| 2015 | 2015-01-01 | June          | ABC    |
| 2014 | 2014-01-05 | June          | ABC    |
| 2016 | 2016-03-05 | Sep           | CDE    |
| 2015 | 2015-03-04 | Sep           | CDE    |
| 2014 | 2014-03-03 | Sep           | CDE    |
+------+------------+---------------+--------+

我有这个查询来查找给定年份和给定产品的最小（最早）日期。有了这个查询，如何在最早的日期没有最早的日期更新Temdate1？

SELECT 
 Year
,CASE 
     WHEN MIN([Date])<entry_date THEN MIN([Date]) 
     ELSE entry_date 
 END AS MDate 
FROM @TempDate1 a
INNER JOIN AllProducts b on a.DeliveryMonth =b.DeliveryMonth AND a.Symbol = b.Symbol
GROUP BY Year,entry_date

Answer 1

你似乎在预期的结果中输错了，或者也许是我

Update a
   set Entry_Date = case when a.Entry_Date> b.Date then b.Date else a.Entry_Date end
from  
   @Tempdate1 a
inner join 
   @AllProducts b 
   on b.Symbol = a.Symbol
   and b.DeliveryMonth = a.DeliveryMonth
   and year(b.[Date]) = a.Year

http://rextester.com/AQXR21093

更新两个表之间的最小日期的表

1 个答案: