Question

我有一个足球游泳池网站。每周，我的朋友都会挑选每场比赛的获胜者。我想比较每个球员与其他球员的选秀权并列出相似的百分比。我发现这个页面帮助我计算了特定周的相似度：Compare group of tags to find similarity/score with PHP/MySQL。感谢Ivar Bonsaksen，他的解决方案很有效！

我现在要做的是显示过去几周每位玩家的累积相似度。

我有3个表要查询：个人资料（spprofiles），游戏（sp6games）和精选（sp6picks）。另一个名为Teams（sp6teams）的表用于获取团队的名称，但这里无关紧要。

Profiles (spprofiles)
+-----------+-------------+
| profileID | profilename |
+-----------+-------------+
| 52        | My Team A   |
| 53        | Some Team B |
+-----------+-------------+

Games (sp6games)
+--------+--------+---------+------+
| gameID | weekID | visitor | home |
+--------+--------+---------+------+
| 1      | 2      | 9       | 21   |
| 2      | 2      | 14      | 6    |
| 17     | 3      | 6       | 9    |
| 18     | 3      | 30      | 21   |
+--------+--------+---------+------+

Picks (sp6picks)
+-----------+--------+------+
| profileID | gameID | pick |
+-----------+--------+------+
| 52        | 1      | 21   |
| 52        | 2      | 6    |
| 52        | 17     | 12   |
| 52        | 18     | 21   |
| 53        | 1      | 9    |
| 53        | 2      | 6    |
| 53        | 17     | 9    |
| 53        | 18     | 21   |
+-----------+--------+------+

本周的查询如下所示：

$weekID = 3; //the current weekID
$profile = 52; //the current ProfileID

SELECT
  targetProfiles.profileID AS targetID,
  sourceProfiles.profileID AS sourceID,
    COUNT(targetProfiles.profileID)
    /
    (((SELECT COUNT(*) FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE profileID = sourceProfiles.profileID AND weekID = $weekID)
      +
    (SELECT COUNT(*) FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE profileID = targetProfiles.profileID AND weekID = $weekID))/2)
  AS similarity
FROM
  spProfiles AS sourceProfiles
  LEFT JOIN
    (SELECT sp6Picks.* FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE weekID = $weekID) AS sourcePicks
    ON (sourcePicks.profileID = sourceProfiles.profileID)
  INNER JOIN
    (SELECT sp6Picks.* FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE weekID = $weekID) AS targetPicks
    ON (sourcePicks.pick = targetPicks.pick AND sourcePicks.profileID != targetPicks.profileID)
  LEFT JOIN
    spProfiles AS targetProfiles
    ON (targetPicks.profileID = targetProfiles.profileID)
WHERE sourceProfiles.profileID = $profile
GROUP BY targetID

如果我分别在几周内运行此查询，我会得到以下结果：

$weekID = 2;
+----------+----------+------------+
| targetID | sourceID | similarity |
+----------+----------+------------+
| 53       | 52       | 0.5000     |
+----------+----------+------------+

$weekID = 3;
+----------+----------+------------+
| targetID | sourceID | similarity |
+----------+----------+------------+
| 53       | 52       | 0.5000     |
+----------+----------+------------+

到目前为止我已经计算出的累积看起来像这样的查询（但我尝试过其他几种变体）。基本上，我只是将WHERE子句更改为包含前几周weekID <= $weekID，并将Games表添加到主FROM子句LEFT JOIN sp6games ON (targetPicks.gameID = sp6games.gameID)。

$weekID = 3; //the current weekID
$profile = 52; //the current ProfileID

SELECT
  targetProfiles.profileID AS targetID,
  sourceProfiles.profileID AS sourceID,
    COUNT(targetProfiles.profileID)
    /
    (((SELECT COUNT(*) FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE profileID = sourceProfiles.profileID AND weekID <= $weekID)
      +
    (SELECT COUNT(*) FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE profileID = targetProfiles.profileID AND weekID <= $weekID))/2)
  AS similarity
FROM
  spProfiles AS sourceProfiles
  LEFT JOIN
    (SELECT sp6Picks.* FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE weekID <= $weekID) AS sourcePicks
    ON (sourcePicks.profileID = sourceProfiles.profileID)
  INNER JOIN
    (SELECT sp6Picks.* FROM sp6Picks LEFT JOIN sp6Games USING (gameID) WHERE weekID <= $weekID) AS targetPicks
    ON (sourcePicks.pick = targetPicks.pick AND sourcePicks.profileID != targetPicks.profileID)
  LEFT JOIN
    spProfiles AS targetProfiles
    ON (targetPicks.profileID = targetProfiles.profileID)
  LEFT JOIN sp6games ON (targetPicks.gameID = sp6games.gameID)
WHERE sourceProfiles.profileID = $profile
GROUP BY targetID, weekID

合并结果应为0.5000，但我得到：

$weekID = 3;
+----------+----------+------------+
| targetID | sourceID | similarity |
+----------+----------+------------+
| 53       | 52       | 0.7500     |
+----------+----------+------------+

问题是COUNT(targetProfiles.profileID)整周没有正确计算，因此similarity值搞砸了。对于较大的数据集，它似乎也不是很有效。

感谢您花时间阅读，并可能提供帮助。

Answer 1

SELECT   t.profileID                 AS target,
         SUM(s.pick=t.pick)/COUNT(*) AS similarity
FROM     sp6picks s
    JOIN sp6picks t USING (gameID)
    JOIN sp6games g USING (gameID)
WHERE    g.weekID    <= 3
     AND s.profileID != t.profileID
     AND s.profileID  = 52
GROUP BY t.profileID

在sqlfiddle上查看。

比较足球比赛与其他球员的数周

1 个答案: