Question

我需要有关mysql查询的帮助。我经历了之前有关ORDER BY和GROUP BY合并的所有讨论，并且我了解了在排序之前执行分组的概念，因此排序将无法按预期进行。这表示由于我在sql方面的经验有限，因此我无法设法使查询适合使用提供的任何示例。可以给有更多经验的人指出正确的方向吗？我有一个链接到数据馈送表的产品集合。我需要按关键字搜索产品表，并为每个数据Feed返回最便宜的产品。可能有多个产品的价格都一样低，而每个数据Feed我只需要退货一次。

这是我到目前为止所拥有的：

select p.*, m.*, d.* from datafeeds as d,  
( 
SELECT   * 
FROM     products AS p
WHERE    1=1
AND (match(p.name) against ('+saucony +"ride iso 2" -women' in boolean mode)) 
AND p.is_custom = 0
ORDER BY merchant_name, 
display_price
)  AS p 
LEFT OUTER JOIN meta as m on p.mykey = m.mykey 
WHERE p.datafeed_id = d.id 
AND (match(p.name) against ('+saucony +"ride iso 2" -women' in boolean mode)) 
AND p.is_custom = 0 
GROUP BY d.merchant_name 
ORDER BY p.display_price asc limit 50

这会为每个数据Feed返回一个产品，但显然不是最便宜的，因为分组是在排序之前执行的

非常感谢您的帮助！

样本数据： https://wtools.io/paste-code/J3b

Answer 1

经过一些实验，我找到了一种使用INNER JOIN的方法

我将其发布为答案，以防万一有人需要

SELECT     p.*
FROM       products AS p
INNER JOIN
           (
                    SELECT   p.datafeed_id,
                             Min(p.display_price) AS minprice
                    FROM     products             AS p,
                             datafeeds            AS d
                    WHERE    p.datafeed_id = d.id
                    AND      (MATCH(p.name) against ('+saucony +"ride iso 2"' IN boolean mode))
                    AND      p.is_custom = 0
                    GROUP BY p.datafeed_id ) AS p2
ON         (
                      p.display_price = p2.minprice
           AND        p.datafeed_id = p2.datafeed_id)
WHERE      (
                      MATCH(p.name) against ('+saucony +"ride iso 2"' IN boolean mode))
AND        p.is_custom = 0
GROUP BY   p.datafeed_id
LIMIT      50

Answer 2

我没有确切的表和数据来测试我的查询，但是根据您的要求，我认为，如果您这样尝试，则应提供所需的输出。

select p.*, m.*, d.* from datafeeds as d, ( SELECT *,min(productPrice) productPrice FROM products AS p WHERE 1=1 and (match(p.name) against ('+saucony +"ride iso 2" -women' in boolean mode)) and p.is_custom = 0 group by p.name,min(productPrice) ORDER BY merchant_name, display_price) as p left outer join meta as m on p.mykey = m.mykey where p.datafeed_id = d.id and (match(p.name) against ('+saucony +"ride iso 2" -women' in boolean mode)) and p.is_custom = 0 group by d.merchant_name,productPrice order by p.display_price asc limit 50

MYSQL将排序依据与分组依据

2 个答案: