SQL NOT IN查询

Question

任何人都可以帮助我解决这个MySQL查询吗？

SELECT p.ProductID, 
     p.StoreID, 
     p.DiscountPercentage 
FROM Products p 
WHERE p.IsSpecial = 1 
    AND p.SpecialDate >= date_sub(now(),interval 15 minute) 
    AND p.DiscountPercentage >= ?DiscountPercentage 
    AND p.ProductID NOT IN (SELECT lf.LiveFeedID 
          From LiveFeed lf 
          WHERE p.ProductID = lf.ProductID 
          AND lf.DateAdded >= date_sub(now(),interval 30 day)) 
    AND p.StoreID NOT IN (SELECT lf.LiveFeedID 
          From LiveFeed lf 
         WHERE p.StoreID = lf.StoreID 
          AND lf.DateAdded >= date_sub(now(),interval 6 hour)) 
ORDER BY p.StoreID, p.DiscountPercentage DESC 

我想加盟ProductID等于不在livefeed表在过去30天，其中STOREID不是在最后6小时livefeed表，但它似乎并不奏效。任何想法我做错了什么？

Answer 1

一目了然，这样看来，你的第一个子查询，应选择ProductID，不LiveFeedID和您的第二子查询，应选择StoreID不LiveFeedID

Answer 2

我太晚了：

SELECT p.ProductID, 
     p.StoreID, 
     p.DiscountPercentage 
    FROM Products p 
    WHERE p.IsSpecial = 1 
    AND p.SpecialDate >= date_sub(now(),interval 15 minute) 
    AND p.DiscountPercentage >= ?DiscountPercentage 
    AND p.ProductID NOT IN (SELECT lf.productid 
           FROM LIVEFEED lf 
           WHERE lf.DateAdded >= DATE_SUB(NOW(), INTERVAL 30 DAY)) 
    AND p.storeid NOT IN (SELECT lf.storeid 
          FROM LIVEFEED lf 
          WHERE lf.DateAdded >= DATE_SUB(NOW(), INTERVAL 6 HOUR)) 
ORDER BY p.StoreID, p.DiscountPercentage DESC 

你正在使用EXISTS语法与相关的子查询...

我想获得每个商店的最高折扣。

在这种情况下，使用：

SELECT p.StoreID, 
     MAX(p.DiscountPercentage) 
    FROM Products p 
    WHERE p.IsSpecial = 1 
    AND p.SpecialDate >= date_sub(now(),interval 15 minute) 
    AND p.DiscountPercentage >= ?DiscountPercentage 
    AND p.ProductID NOT IN (SELECT lf.productid 
           FROM LIVEFEED lf 
           WHERE lf.DateAdded >= DATE_SUB(NOW(), INTERVAL 30 DAY)) 
    AND p.storeid NOT IN (SELECT lf.storeid 
          FROM LIVEFEED lf 
          WHERE lf.DateAdded >= DATE_SUB(NOW(), INTERVAL 6 HOUR)) 
GROUP BY p.storeid 
ORDER BY p.StoreID, p.DiscountPercentage DESC