如何运行哪个查询以选择SQL表中每个值组的最高值？

问题描述

| 我有一张

bids

的表格（例如，像eBay出价）：

bid_id | bid_from_user | bid_for_auction | bid_price
1      | 150           | 1               | 20
2      | 453           | 1               | 30
3      | 42            | 1               | 50
4      | 12            | 2               | 12
5      | 60            | 2               | 20

我只需要选择每个具有最高当前出价的bid2ѭ，因此我的结果应如下所示：

bid_for_auction | bid_price
1               | 50
2               | 20

我将如何去做呢？     

解决方法

使用GROUP BY

SELECT bid_for_auction,MAX(bid_price) AS bid_price
FROM bids GROUP BY bid_for_auction;

    ,

SELECT bid_for_auction,MAX(bid_price)
FROM bids
GROUP BY bid_for_auction

    ,这应该可以解决问题：

SELECT
 `bid_for_auction`,MAX(`bid_price`)
FROM `bids`
GROUP BY `bid_for_auction`

    ,SELECT bid_for_auction，MAX（bid_price）FROM bids GROUP BY bid_for_auction