mysql - SQL查询: Current lowest price of products

Question

我正在为项目的 SQL 查询而苦苦挣扎。

给出了下表:

tblProduct => (proProductID, proProductName)
tblSeller => (selSellerID, selSellerName)
linkProductSeller => (linkID, linkProductID, linkSellerID, linkPrice, linkShippingPrice, linkDatetime)

每次卖家的产品价格/运费发生变化时，都会在 linkProductSeller 中添加新行。

我需要了解产品当前的最低价格/运费组合和卖家。

为了获取产品的所有当前价格，我使用此查询

SELECT linkProductID, linkSellerID, linkPrice+linkShippingPrice as price, linkDatetime
FROM linkProductSeller AS a
WHERE linkDatetime = (
    SELECT MAX(linkDatetime)
    FROM linkProductSeller AS b
    WHERE a.linkProductID = b.linkProductID
AND a.linkSellerID = b.linkSellerID)
ORDER BY linkProductID ASC, price ASC, linkDatetime DESC

感谢您的支持。

Answer 1

您需要的所有数据都在 linkProductSeller 中，因此这应该可行

select l.linkProductId, min(linkPrice + linkShippingPrice) as minPrice
  from linkProductSeller l,
       (select linkProductID, linkSellerId, max(linkDateTime) as linkDateTime
          from linkProductSeller 
         group by linkProductID, linkSellerId) m
 where l.linkProductID = m.linkProductID
   and l.linkSellerID = m.linkSellerID
   and l.linkDateTime = m.linkDateTime
 group by linkProductId