1
我需要一個遊戲中排名最高的玩家列表。等級是即時計算的,數據來自兩個表格。我設法以正確的方式訂購它們,但是@rank:= 0 - > @rank:= @ rank + 1技巧,其中一個名爲rank的額外字段正在計算玩家對應特定位置訂購參數,不返回正確的等級順序。這是我有:MySQL排名(排名最高的用戶)
SET @rank := 0;
SELECT
@overall := u_p_s.exploration + u_p_s.story + u_p_s.collection + u_p.experience AS overall,
@rank := @rank + 1 AS rank,
u.nick, u.user_id, u_p_s.exploration, u_p_s.story, u_p_s.collection, u_p.experience
FROM user AS u
INNER JOIN user_profile_stats AS u_p_s ON u_p_s.user_id = u.user_id
INNER JOIN user_profile AS u_p ON u_p.user_id = u.user_id
ORDER BY overall DESC
LIMIT 0 ,20;
結果是正確的整體秩序但不正確排序。我總是可以對行進行計數並獲得應用程序層的排名,但我仍然需要知道我的查詢在這裏出了什麼問題。如果您有任何關於如何計算特定用戶排名的建議,我願意接受建議。我看到很多類似的問題,但是他們沒有一個在飛行中計算排名參數(整體),並且由於我不是MySql最好的,我請您尋求幫助。謝謝。
解決方案:
SET @rank:=0;
SELECT
@rank := @rank +1 AS rank,
nick, user_id, story, overall, collection, experience, exploration
FROM (
SELECT @overall := u_p_s.exploration + u_p_s.story + u_p_s.collection + u_p.experience AS overall,
u.nick, u.user_id, u_p_s.story, u_p.experience, u_p_s.collection, u_p_s.exploration
FROM user AS u
INNER JOIN user_profile_stats AS u_p_s ON u_p_s.user_id = u.user_id
INNER JOIN user_profile AS u_p ON u_p.user_id = u.user_id
ORDER BY overall DESC
LIMIT 0 , 20
) AS result
肯定的,問題是,我需要一個派生表。謝謝你,這已經很糟糕了。 – chosta 2011-03-14 20:51:20
謝謝......它真的幫了很多.. – 2014-04-22 09:02:24