SQL NOT IN查询

Question

谁能帮我这个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

我正在尝试加入，过去30天内ProductID不在livefeed表中，而storeid过去6小时不在livefeed表中，但似乎不起作用。 知道我在做什么错吗？

Answer 1

乍一看，您的第一LiveFeedID查询应该选择ProductID而不是LiveFeedID而第二LiveFeedID查询应该选择StoreID而不是LiveFeedID

Answer 2

我为时已晚：

  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

您正在使用EXISTS语法和相关的子查询...

我正在尝试为每家商店获得最高折扣。

在这种情况下，请使用：

  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