group_concat 不适用于计数

Question

我用

SELECT 
GROUP_CONCAT(DISTINCT `a`.`IDperson` SEPARATOR ', ') AS `person`,
COUNT(`a`.`IDjobs`) AS `total`
FROM
`a`
GROUP BY `a`.`ID_person`
ORDER BY `total` DESC

我需要的是返回类似

的结果

person        total
 2342           98
 1342           75
 3844           70
 1705           62
 3309           53
 5918, 1328     52
 1503, 1890     46
21004, 6536     45

但是没用它返回的结果就像 GROUP_CONCT 不工作

    person        total
     2342           98
     1342           75
     3844           70
     1705           62
     3309           53
     5918           52
     1328           52
     1503           46
     1890           46
    21004           45
     6536           45

Answer 1

似乎你需要根据计数的数量进行 concat grouing，所以你应该

select GROUP_CONCAT(DISTINCT t.IDperson SEPARATOR ', ') AS person,  t.total
from (
      select DISTINCT a.IDperson as IDPerson, COUNT(a.IDjobs) AS `total`
      FROM a
      GROUP BY a.ID_person ) t 
group by t.total
ORDER BY t.total DESC

Answer 2

我推测你想要：

SELECT numjobs, GROUP_CONAT(idperson SEPARATOR ', ' ORDER BY idperson) as persons
FROM (SELECT idperson, COUNT(*) as numjobs
      FROM a
      GROUP BY idperson
     ) ap
GROUP BY numjobs
ORDER BY numjobs DESC;

Answer 3

GROUP_CONCAT() 完美运行。因为你 GROUP BY `a`.`ID_person`，每组只包含一个 `a`.`ID_person` 的值，因此你得到的结果。你可能想要 `GROUP BY `a`.`IDjobs`:

SELECT 
    GROUP_CONCAT(DISTINCT `a`.`IDperson` SEPARATOR ', ') AS `person`,
    COUNT(`a`.`IDjobs`) AS `total`
FROM
   `a`
GROUP BY `a`.`IDjobs`
ORDER BY `total` DESC

group_concat 不适用于计数

group_concat doesn't work with count

mysql

count

group-concat