如何訂購具有計數和比率的MySQL查詢

Question

我在訂購具有計數和比率的MySQL查詢時遇到了麻煩。

這是我目前使用

$getKillers = mysql_query("SELECT `killer`, `killed`, count(`killer`), count(`killed`) FROM `kills` GROUP BY `killer` ORDER BY count(`killer`)/count(`killed`) DESC LIMIT {$limit}"); 

此代碼的數據庫結構，我使用

CREATE TABLE `kills` (
    `id` int(11) NOT NULL AUTO_INCREMENT, 
    `killer` varchar(20) NOT NULL COMMENT 'The player who scored the kill', 
    `killed` varchar(20) NOT NULL COMMENT 'The player who was killed', 
    PRIMARY KEY (`id`), 
    KEY `killer` (`killer`,`killed`) 
) ENGINE=InnoDB AUTO_INCREMENT=680633 DEFAULT CHARSET=utf8 COMMENT='PVP Log'; 

-- ---------------------------- 
-- Records of kills 
-- ---------------------------- 
INSERT INTO `kills` VALUES ('1', 'Player1', 'Player2'); 
INSERT INTO `kills` VALUES ('2', 'Player1', 'Player3'); 
INSERT INTO `kills` VALUES ('3', 'Player2', 'Player3'); 
INSERT INTO `kills` VALUES ('4', 'Player2', 'Player1'); 
INSERT INTO `kills` VALUES ('5', 'Player1', 'Player2'); 
INSERT INTO `kills` VALUES ('6', 'Player3', 'Player3'); 
INSERT INTO `kills` VALUES ('7', 'Player2', 'Player3'); 
INSERT INTO `kills` VALUES ('8', 'Player3', 'Player1'); 

我想這個SQL使用mysql_fetch_array在PHP中顯示前PVP與KDR（殺死死亡比率）是殺手殺手。這是他們殺死他人的次數。

感謝您的幫助！

Answer 1

嘗試此查詢：

SELECT * , (SELECT COUNT(1) 
      FROM kills b 
      WHERE nested.killer = b.killed 
      ) AS killed_cnt 
FROM ( 
    SELECT `killer` , COUNT( `killer`) AS kill_cnt 
    FROM `kills` a 
    GROUP BY `killer` 
) nested 
ORDER BY kill_cnt/killed_cnt DESC 
LIMIT 10