PHP MYSQL組排名查詢

Question

CREATE TABLE `players` (
 `pid` int(2) NOT NULL AUTO_INCREMENT,
 `name` varchar(50) NOT NULL,
`team` varchar(20) NOT NULL,
`age` int(2) NOT NULL,
PRIMARY KEY (`pid`),
UNIQUE KEY `name` (`name`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1;


INSERT INTO `players` (`pid`, `name`, `age`, `team`) VALUES
(1, 'Samual', 25, 'aa'),
(2, 'Vino', 20, 'bb'),
(3, 'John', 20, 'dd'),
(4, 'Andy', 22, 'cc'),
(5, 'Brian', 21, 'dd'),
(6, 'Dew', 24, 'xx'),
(7, 'Kris', 25, 'qq'),
(8, 'William', 26, 'cc'),
(9, 'George', 23, 'nn'),
(10, 'Peter', 19, 'aa'),
(11, 'Tom', 20, 'aa'),
(12, 'Andre', 20, 'aa');

在上表中，我希望該查詢以分數降序獲取球員的排名。

SELECT pid, name, age, team, rank FROM
(SELECT pid, name, age, team,
@curRank := IF(@prevRank = age, @curRank, @incRank) AS rank, 
@incRank := @incRank + 1, 
@prevRank := age
FROM players p, (
SELECT @curRank :=0, @prevRank := NULL, @incRank := 1
) r 
ORDER BY age DESC) s WHERE team='aa'

它給了我下面的結果：

Name        |     Age    | Rank  
####--------------------------------   
Samual      |     25     | 2    
Tom         |     20     | 8    
Andre       |     20     | 8    
Peter       |     19     | 12  

但我希望以這種方式返回結果：

Name        |     Age    | Rank  
####--------------------------------   
Samual      |     25     | 1    
Tom         |     20     | 2    
Andre       |     20     | 2    
Peter       |     19     | 4   

因此，通過查詢可以給我特定組內的排名。

Answer 1

您需要將查詢中的where子句移動為

SELECT pid, 
name, 
age, 
team, 
rank 
FROM (
 SELECT pid, name, age, team,
 @curRank := IF(@prevRank = age, @curRank, @incRank) AS rank, 
 @incRank := @incRank + 1, 
 @prevRank := age
 FROM players p, (SELECT @curRank :=0, @prevRank := NULL, @incRank := 1) r
 WHERE team='aa'
 ORDER BY age DESC
) s