MYSQl - Group_Concat中的元素计数

Question

我是MYSQL的新手，需要在group_concat语句中提供一些帮助。我有下表

Seller Merchant CustomerID
S1     M1       C1
S1     M1       C1
S1     M1       C2
S1     M1       C3
S1     M1       C4
S2     M2       C5
S2     M2       C6
S3     M3       C6

对于同一卖家和商家的组合，所有具有不同customerID的项目以及重复次数的计数。

我能够使用group_concat导出唯一客户IDS的计数，但无法获得计数。

SELECT * , LENGTH(CUSTIDS) - LENGTH(REPLACE(CUSTIDS,',',''))+1 AS COUNT_OF_CUSTIDS
FROM (SELECT SELLER, MERCHANT, GROUP_CONCAT(CUSTOMERID SEPARATOR '|') AS CUSTIDS
FROM TABLE
GROUP BY SELLER, MERCHANT
HAVING COUNT(DISTINCT CUSTOMERID ) >1 
)

这给了我以下结果

Seller Merchant CustomerID    COUNT_OF_CUSTIDS
S1     M1       C1,C2,C3,C4   4
S2     M2       C5,C6         2

而我想要下面的内容

Seller Merchant CustomerID                 COUNT_OF_CUSTIDS
S1     M1       C1(2),C2(1),C3(1),C4(1)    4
S2     M2       C5(1),C6(1)                2

Answer 1

您需要先在seller / merchant / customerid级别聚合才能获得计数。然后你可以继续你的聚合：

  SELECT SELLER, MERCHANT,
         COUNT(*) as COUNT_OF_CUSTIDS,
         GROUP_CONCAT(CUSTOMERID, ' (', cnt, ')' SEPARATOR '|') AS CUSTIDS
  FROM (SELECT SELLER, MERCHANT, COUNT(*) as cnt
        FROM TABLE
        GROUP BY SELLER, MERCHANT, CUSTOMERID
       ) t
  GROUP BY SELLER, MERCHANT
  HAVING COUNT(* ) > 1