Question

我有一张表格，其中记录了每个用户在其个人资料页面上的访问次数。鉴于表条目类似于

 id user time ip

是否可以使用sigle查询显示某个用户访问的排名？

示例：您的排名：＃400 - 表示用户在页面点击次数上排名为400。

Answer 1

这是一种方法。最里面的子查询计算每个用户的访问次数。下一个子查询计算一个名为@uservisits的变量，该变量存储给定用户的值。外部查询然后使用它来计算排名：

select count(*) as rank
from (select user, numvisits, @uservisits := if(user = $user, numvisits, @uservisits)
      from (select user, count(*) as numvisits
            from table t
            group by user
           ) t cross join
           (select @uservisits := 0) init
     ) t
where numvisits >= @uservisits

Answer 2

这种事情？

SELECT  @rank := @rank+1 AS rank, province, cityCount
    FROM
      ( SELECT  @rank := 0 ) z
    JOIN
      ( SELECT  province, COUNT(*) AS cityCount
            FROM  Canada
            GROUP BY  province
      ) x
    ORDER BY  cityCount DESC;
+------+---------------------------+------------+
| rank | province                  | cityCount  |
+------+---------------------------+------------+
|    1 | Quebec                    |       1045 |
|    2 | Ontario                   |        891 |
|    3 | British Columbia          |        716 |
|    4 | Saskatchewan              |        573 |
|    5 | Alberta                   |        573 |
|    6 | Newfoundland and Labrador |        474 |
|    7 | Nova Scotia               |        331 |
|    8 | Manitoba                  |        299 |
|    9 | New Brunswick             |        210 |
|   10 | Yukon                     |        114 |
|   11 | Nunavut                   |        107 |
|   12 | Northwest Territories     |         94 |
|   13 | Prince Edward Island      |         57 |
+------+---------------------------+------------+

排名多个条目sql

2 个答案: