我已经提出了我正在尝试做的事情的样本
http://sqlfiddle.com/#!2/514d2/2
此演示会查找“出价”表格中不是每个listing_id出价最高的所有行。我需要做的是查找所有列表，其中$ userid（在这种情况下是用户1）是出价最高者。
有人可以帮我解决这个问题吗？
对于那些不使用SQLFiddle的人......
SQL：
SELECT listings.end_date,
listings.user_id,
listings.title,
listings.auc_fp,
listings.id,
listings.auc_image1
FROM listings
INNER JOIN
(SELECT
listing_id,
user_id,
bid maxBid
FROM bids
WHERE bid
NOT IN
(SELECT MAX(bid)
FROM bids)
GROUP BY
listing_id,
user_id)
bids ON
listings.id = bids.listing_id
WHERE bids.user_id=1
AND listings.end_date > NOW()
ORDER BY listings.list_ts DESC
此查询成功找到$ userid已设置出价的所有商家信息，但不是最高出价者。我想查找$ userid已经出价的所有商家信息，并且是最高出价者。
答案 0 :(得分：2)
原始查询可以重新格式化，以便于阅读：
SELECT listings.end_date,
listings.user_id,
listings.title,
listings.auc_fp,
listings.id,
listings.auc_image1
FROM listings
JOIN (SELECT listing_id,
user_id,
bid maxBid
FROM bids
WHERE bid NOT IN (SELECT MAX(bid) FROM bids)
GROUP BY listing_id, user_id
) AS bids
ON listings.id = bids.listing_id
WHERE bids.user_id = 1
AND listings.end_date > NOW()
ORDER BY listings.list_ts DESC
我注意到列为maxBid的列不一定是任何商家信息的最高出价。此查询也仅适用于仍处于打开状态的商家信息。我不相信它会产生预期的答案;排除的唯一出价是包含任何商家信息的总出价最高的出价。
真正的问题是：
查找$ userid（= 1）已设置出价且 出价最高者的所有当前打开的商家信息。
时间做TDQD - 测试驱动的查询设计;我的大脑工作速度不够快，无法一次完成。
SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1
SELECT l.*
FROM listings AS l
JOIN (SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1
) AS u
ON l.id = u.listing_id
SELECT l.*
FROM listings AS l
JOIN (SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1
) AS u
ON l.id = u.listing_id
WHERE l.end_date > NOW()
您可以而且应该将*替换为您感兴趣的确切列。如果您需要出价详情，也可以获得这些。
需要进行一些小的语法更改 - NOW（）被CURRENT YEAR TO SECOND取代 - 但这只会影响最后一个查询。 DDL需要更多工作才能将语法转换为更接近DBMS的中性格式; MySQL有一些奇怪的约定。
未来读者请注意：将NOW()或CURRENT YEAR TO SECOND替换为2012-12-29 12:37:43等值，以获得相同的结果。数据中的列表将从2013-01-10 00：00：001开始到期。
查询1：
SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id;
输出1：
listing_id maxbid
34 95.37
40 103.00
38 507.00
41 94.00
48 76.00
6469 22.00
6472 5.00
37 511.00
31 100.00
查询2：
SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1;
输出2：
listing_id
34
37
48
6469
6472
查询3：
SELECT l.end_date, l.user_id, l.title, l.id
FROM listings AS l
JOIN (SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1
) AS u
ON l.id = u.listing_id;
输出3： end_date user_id标题ID 2013-01-09 08:11:16 1圣诞树6469 2013-01-11 09:17:31 3另一个测试项目6472
查询4
SELECT l.end_date, l.user_id, l.title, l.id
FROM listings AS l
JOIN (SELECT b.listing_id
FROM bids AS b
JOIN (SELECT listing_id, MAX(bid) AS maxBid
FROM bids
GROUP BY listing_id
) AS m
ON m.listing_id = b.listing_id AND m.maxBid = b.bid
WHERE b.user_id = 1
) AS u
ON l.id = u.listing_id
WHERE l.end_date > CURRENT YEAR TO SECOND;
输出4：
end_date user_id title id
2013-01-09 08:11:16 1 Christmas Tree 6469
2013-01-11 09:17:31 3 Another test item 6472
答案 1 :(得分：1)
这应该使用左连接来执行您需要的操作，以确保每个产品没有更好的出价;
SELECT DISTINCT listings.end_date, listings.user_id, listings.title,
listings.auc_fp, listings.id, listings.auc_image1
FROM listings
JOIN bids b1
ON b1.listing_id=listings.id
LEFT JOIN bids b2
ON b2.listing_id=listings.id AND b1.bid < b2.bid
WHERE b1.user_id = 1
AND b2.bid IS NULL
AND listings.end_date > NOW()