反轉分組查詢的序列號

Question

以下查詢根據用戶投了多少次來計票...我想知道特定用戶隊列中的＃號。

SELECT @s:=@s+1 serial_number, user_id, COUNT(slug_owner) as cnt 
FROM `votes_queue`,(SELECT @s:= 0) AS s 
GROUP BY slug_owner 
ORDER BY cnt DESC 

serial_number | user_id | cnt  
3 | 19 | 8 
2 | 14 | 4 
1 | 13 | 2 

從本質上講，我需要的數字在SERIAL_NUMBER列被扭轉，所以我可以告訴大家，用戶13是一個基於投票＃3 ..

Answer 1

產生有序計數後分配序列號：

SELECT @s:=@s+1 serial_number, temp.* 
FROM (
    SELECT user_id, COUNT(slug_owner) as cnt 
    FROM `votes_queue`, 
    GROUP BY slug_owner 
    ORDER BY cnt DESC 
) temp, (SELECT @s:= 0) AS s 

Answer 2

由於GROUP BY和變量不混合，序列號不會被反轉。 ORDER BY很好。您可以使用@ hjpotter92的解決方案，但下面也解決了這個問題：

SELECT (@rn := @rn + 1) as serial_number, t.* 
FROM (SELECT serial_number, user_id, COUNT(slug_owner) as cnt 
     FROM `votes_queue` 
     GROUP BY slug_owner 
    ) t CROSS JOIN 
    (SELECT @rn := 0) params 
ORDER BY cnt DESC; 

我認爲性能是一樣的。我提供這個答案只是爲了澄清實際問題。