Question

如何合并以下两个查询以向我提供具有总体排名的特定用户事件？

查询1.根据投票数返回事件的排名。

 SELECT e.guid, e.name, e.votes, @curRank := @curRank + 1 AS rank
 FROM event e, (SELECT @curRank := 0) r
 ORDER BY votes DESC;

查询2.返回特定用户的事件。

SELECT e.guid, e.name, e.votes
FROM user_event ue
JOIN event e
ON e.guid = ue.event_uid
WHERE ue.user_uid = '123';

活动表

guid | name | votes
-------------------
abc   event1  10
def   event2  5
ghi   event3  15

用户事件表

user_event_id | event_guid | user_uid 
--------------------------------------
       1          abc           123
       2          def           123 
       3          ghi           456

组合查询应返回user123

guid   name   votes  rank
abc | event1 | 10 |    2
def | event2 | 5  |    3

或者对于用户456：

guid  name    votes   rank
ghi | event3 | 15 |    1

Answer 1

这适用于您的版本：

SELECT r.* FROM user_event ue
JOIN(
    SELECT e.guid, e.name, e.votes, @curRank := @curRank + 1 AS rank
    FROM event e, (SELECT @curRank := 0) r
    ORDER BY votes DESC
 ) AS r ON r.guid = ue.event_guid
WHERE ue.user_uid = 123

具有总体排名的特定用户的MySQL Return事件

1 个答案: