用户活动提要（ala facebook）。如何对类似的活动进行分组？

Question

在我正在进行的电影数据库项目中，每个用户都有一个活动源。我想对类似的活动进行分组，例如 Facebook 的做法，但差别不大。

例如，如果用户为一部电影写了评论，一分钟后他也为该电影投票，五分钟后他上传了该电影的预告片，我想在活动源中一起显示（分组） .

我认为最好是在查询数据库时对其进行分组，但我认为在这种情况下这是不可能的，因为我使用了一个非常大的 JOIN 来获取所有数据：

SELECT ua.datetime, ua.imdbID, ua.personID, sa.activityID, sa.activity, m.title, m.year, p.name, umv.vote, upv.vote, r.review, t.youTubeID, ps.filename, ph.filename
FROM user_activity ua
JOIN sys_activities sa ON ua.activityID = sa.activityID
LEFT OUTER JOIN movies m ON ua.imdbID = m.imdbID
LEFT OUTER JOIN persons p ON ua.personID = p.personID
LEFT OUTER JOIN user_movies_vote umv ON umv.userID = ua.userID AND umv.imdbID = ua.imdbID
LEFT OUTER JOIN user_persons_vote upv ON upv.userID = ua.userID AND upv.personID = ua.personID
LEFT OUTER JOIN reviews r ON r.userID = ua.userID AND r.imdbID = ua.imdbID
LEFT OUTER JOIN (
        select imdbID, userID, youTubeID, max(hd) as MaxTrailerStatus
        from trailers
        group by imdbID
        ) t ON ua.imdbID = t.imdbID AND ua.userID = t.userID
LEFT OUTER JOIN (
        select imdbID, filename, max(main) as MaxPosterStatus
        from posters
        group by imdbID
        ) ps ON ua.imdbID = ps.imdbID
LEFT OUTER JOIN (
        select personID, filename, max(main) as MaxPhotosStatus
        from photos
        group by personID
        ) ph ON ua.personID = ph.personID
WHERE ua.userID = ?
ORDER BY ua.datetime DESC

我想知道如何通过修改查询或使用 PHP 来做到这一点。 谢谢。

Answer 1

您可能会根据正在修改的项目的项目 ID 进行分组 - 在本例中类似于：ua.imdbID。

一旦这样做，您将丢失其他数据行，因此您将使用 GROUP_CONCAT 来获取所有相关 ID。

GROUP_CONCAT(sa.activityID);

所以你的最终结果是：

SELECT ua.datetime, ua.imdbID, ua.personID, GROUP_CONCAT(sa.activityID), sa.activity, m.title, m.year, p.name, umv.vote, upv.vote, r.review, t.youTubeID, ps.filename, ph.filename
FROM user_activity ua
JOIN sys_activities sa ON ua.activityID = sa.activityID
LEFT OUTER JOIN movies m ON ua.imdbID = m.imdbID
LEFT OUTER JOIN persons p ON ua.personID = p.personID
LEFT OUTER JOIN user_movies_vote umv ON umv.userID = ua.userID AND umv.imdbID = ua.imdbID
LEFT OUTER JOIN user_persons_vote upv ON upv.userID = ua.userID AND upv.personID = ua.personID
LEFT OUTER JOIN reviews r ON r.userID = ua.userID AND r.imdbID = ua.imdbID
LEFT OUTER JOIN (
        select imdbID, userID, youTubeID, max(hd) as MaxTrailerStatus
        from trailers
        group by imdbID
        ) t ON ua.imdbID = t.imdbID AND ua.userID = t.userID
LEFT OUTER JOIN (
        select imdbID, filename, max(main) as MaxPosterStatus
        from posters
        group by imdbID
        ) ps ON ua.imdbID = ps.imdbID
LEFT OUTER JOIN (
        select personID, filename, max(main) as MaxPhotosStatus
        from photos
        group by personID
        ) ph ON ua.personID = ph.personID
WHERE ua.userID = ?  GROUP BY ua.imdbID


ORDER BY ua.datetime DESC