如何使用MySQL获取最近的日期

Question

如何使用MySQL获取最近的日期？我尝试了max，但没有得到我想要的结果。我的表看起来像这样：

+---------+---------+-----------------------+--------+------------+---------+ 
| Name | idStore | Name     | idItem | date  | price | 
+---------+---------+-----------------------+--------+------------+---------+ 
| walmart |  1 | Red Delicious Apples |  1 | 2011-10-22 | 0.98000 | 
| walmart |  1 | Red Delicious Apples |  1 | 2011-10-28 | 0.98000 | 
| walmart |  1 | Red Delicious Apples |  1 | 2011-10-28 | 0.98000 | 
| walmart |  1 | Red Delicious Apples |  1 | 2011-11-22 | 0.98000 | 
| walmart |  1 | Honeycrisp Apples  |  2 | 2011-10-22 | 1.98000 | 
| walmart |  1 | Sonya Apples   |  3 | 2011-10-22 | 2.88000 | 
| walmart |  1 | Gold Delicious Apples |  4 | 2011-10-22 | 0.98000 | 
| walmart |  1 | Sweet Tango Apples |  5 | 2011-10-22 | 2.48000 | 
| walmart |  1 | Granny Smith Apples |  6 | 2011-10-22 | 1.28000 | 
| walmart |  1 | Fugi Apples   |  7 | 2011-10-22 | 1.38000 | 
+---------+---------+-----------------------+--------+------------+---------+ 

我想这个表：

+---------+---------+-----------------------+--------+------------+---------+ 
| Name | idStore | Name     | idItem | date  | price | 
+---------+---------+-----------------------+--------+------------+---------+ 
| walmart |  1 | Red Delicious Apples |  1 | 2011-11-22 | 0.98000 | 
| walmart |  1 | Honeycrisp Apples  |  2 | 2011-10-22 | 1.98000 | 
| walmart |  1 | Sonya Apples   |  3 | 2011-10-22 | 2.88000 | 
| walmart |  1 | Gold Delicious Apples |  4 | 2011-10-22 | 0.98000 | 
| walmart |  1 | Sweet Tango Apples |  5 | 2011-10-22 | 2.48000 | 
| walmart |  1 | Granny Smith Apples |  6 | 2011-10-22 | 1.28000 | 
| walmart |  1 | Fugi Apples   |  7 | 2011-10-22 | 1.38000 | 
+---------+---------+-----------------------+--------+------------+---------+ 

我有很难搞清楚了这一点。谢谢！

Answer 1

在线实例查询

http://data.stackexchange.com/stackoverflow/q/118881/how-can-i-get-the-most-resent-date-using-mysql

SELECT NameStore, idStore, Name, idItem, max(date) AS date, price 
FROM tablename 
GROUP by NameStore, idStore, Name, idItem, price 
ORDER BY date DESC, idItem ASC 

Answer 2

把这个末ORDER BY date DESC

因此，使它看起来像这样：

SELECT * FROM `tablename` ORDER BY `date` DESC 

在上面的SQL语句使用DISTINCT(Name)或GROUP BY Name，就会使一个项目弹出一次。

Answer 3

您可以通过使用组：

select NameStore, idStore, Name, idItem, max(date) date, price 
from table 
group by NameStore, idStore, Name, idItem, price 

Answer 4

您必须使用GROUP BY条款是这样的：

SELECT Name, idStore, Name, idItem, date, price 
FROM mytable 
GROUP BY idItem 
ORDER BY date DESC, idItem DESC; 

更改使用DESC或ASC顺序方向。您可以通过阅读文档了解更多信息。

Answer 5

见SQL Select only rows with Max Value on a Column

SELECT yt1.* 
FROM yourtable yt1 
LEFT OUTER JOIN yourtable yt2 ON (yt1.idItem = yt2.idItem AND yt1.date < yt2.date) 
WHERE yt2.idItem IS NULL;