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当两栏以上具有相同价值时,单行回归
原标题:Return a single row when more than two columns have the same value
  • 时间:2024-02-19 00:47:18
  •  标签:
  • mysql

在两个具体栏中,如果我拥有两个或两个以上具有相同价值的增长,我只需要一行。 选定的行文必须是国名栏中的最新行文。

SELECT * FROM `history` WHERE productId IN (166, 2915) ORDER BY history.value;

OBS:产品 因此,我可以有20多个项目。 这只是一个例子。

ACTUAL RETURN

id supermarketId productId value date
2722 2 2915 7.98 2023-11-19 00:00:00
180 3 166 7.99 2023-07-23 00:00:00
1639 2 166 8.98 2023-06-05 00:00:00
4251 2 166 8.98 2024-02-17 00:00:00
4220 2 2915 8.98 2024-02-17 00:00:00
2759 3 2915 9.99 2023-11-15 00:00:00

DESIRED RETURN

id supermarketId productId value date
180 3 166 7.99 2023-07-23 00:00:00
4251 2 166 8.98 2024-02-17 00:00:00
4220 2 2915 8.98 2024-02-17 00:00:00
2759 3 2915 9.99 2023-11-15 00:00:00

我尝试:

SELECT * FROM `history` WHERE productId IN (166, 2915) 
AND date = (SELECT MAX(date) FROM history) ORDER BY history.value;

但是,一些增长已经消除:

id supermarketId productId value date
4251 2 166 8.98 2024-02-17 00:00:00
4220 2 2915 8.98 2024-02-17 00:00:00
问题回答

如果我理解这个问题,那么在提问之后,应该解决这个问题。

SELECT A.* FROM [history] A
INNER JOIN (SELECT [productId], supermarketId, MAX(date) as date
            FROM [history]
            GROUP BY [productId], supermarketId
    
            HAVING COUNT(*) >= 1 and productId in (2915, 166)) as B
ON A.[productId] = B.[productId] AND A.supermarketId = B.supermarketId and A.date = b.date

首先,检查你的格式,在166至2915之间使用。





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