Question

我有一个像这样的RANK表

+-------------+---------------------+------+-----+---------+----------------+
| Field       | Type                | Null | Key | Default | Extra          |
+-------------+---------------------+------+-----+---------+----------------+
| uid         | VARCHAR(50) unsigned | NO   | PRI | NULL    |               |
| steps       | int(20) unsigned    | NO   |     | NULL    |                |
+-------------+---------------------+------+-----+---------+----------------+

我希望通过DESC对步骤进行排序，并使用主要的uid获取特定行的行位置。

我可以按

排序

SELECT uid, steps FROM RANK ORDER BY steps DESC

但我不知道如何使用uid获取特定行的行位置。我在stackoverflow上看到了一些线程，并在我们的数据库服务器上尝试了它，但它没有成功。有没有办法做到这一点？

我试过了：

SET @rank=0; 
SELECT @rank:=@rank+1 AS rank, steps, COUNT(*) as ordercount 
FROM RANK 
GROUP BY steps 
ORDER BY ordercount DESC;

但它没有得到我的任何结果

与sequelizejs

async function getUserData(uid) {
    var query = ""
    query += "SELECT rank, total_steps_value FROM ("
    query += "    SELECT @rank := @rank + 1 AS rank, user_id, total_steps_value"
    query += "    FROM RANK"
    query += "    CROSS JOIN (SELECT @rank := 0) AS var"
    query += "    ORDER BY total_steps_value DESC) AS x"
    query += `WHERE user_id = ${mysql.escape(uid)}`

    let res = await models.sequelize.query(query)
    console.log("RES", res)
}

我收到此错误

SequelizeDatabaseError: ER_PARSE_ERROR: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'user_id = '10208360871964156'' at line 1

Answer 1

您不需要COUNT(*)，因为您没有尝试按计数排名，您只想按列值进行排名。

SELECT @rank := @rank + 1 AS rank, uid
FROM RANK
CROSS JOIN (SELECT @rank := 0) AS var
ORDER BY steps DESC

要获取特定uid的排名，请将其放在子查询中。

SELECT rank FROM (
    SELECT @rank := @rank + 1 AS rank, uid
    FROM RANK
    CROSS JOIN (SELECT @rank := 0) AS var
    ORDER BY steps DESC) AS x
WHERE uid = '123545'

Answer 2

您还可以使用以下方式获取特定行的排名：

select count(*)
from rank r
where r.score >= (select r2.score from rank r2 where r2.uid = ?);

mysql获取唯一id的行位置

2 个答案: