如何将 group_concat 与 group by 一起使用答案

【问题标题】：how to use group_concat with group by如何将 group_concat 与 group by 一起使用
【发布时间】：2012-11-12 11:19:25
【问题描述】：

这是我的查询：

 SELECT 
    O.OrderId,
    O.Number,
    (SELECT 
            CONCAT(A.Detail, ' ', C.Name, ' / ', Ci.Name)
        FROM
            kobiakinlar.Address AS A
                INNER JOIN
            County AS C ON C.CountyId = A.CountyId
                INNER JOIN
            City AS Ci ON C.CityId = Ci.CityId
        WHERE
            UserId = O.UserId) AS UserAddress,
    (SELECT 
            CASE
                    WHEN O.Status = 0 THEN 'Onay Bekliyor'
                    WHEN O.Status = 1 THEN 'Onaylandı'
                    WHEN O.Status = 2 THEN 'Reddedildi'
                END
        ) Status,
    O.Creation,
    (SELECT 
            CASE
                    WHEN O.IsDelivered = 0 THEN 'Teslim Edilmedi'
                    ELSE 'Teslim Edildi'
                END
        ) IsDelivered,
    SUM(T.Price) Price,
    GROUP_CONCAT(T.NAME) Products
FROM
    kobiakinlar.order O
        INNER JOIN
    (SELECT  
        P.Name, op.OrderId, op.Price
    FROM
        kobiakinlar.product P
    JOIN kobiakinlar.orderproduct op ON op.ProductId = P.productId
 ) T ON O.orderId = T.orderId
        INNER JOIN
    address A ON A.AddressId = O.AddressId

但我想试试这个：

我该怎么办？你对我有什么建议吗？

【问题讨论】：

你的SQL语句中没有group_by？
@ManseUK，是的，因为，我放了但它没有用......而且我找不到我应该把我的小组放在哪里
详细说明您需要对哪些列进行分组等。从屏幕截图中无法理解。
@nawfal，我需要用 orderId 分组...
看不到数据很困难。您确定订单 id = 5 和 8 的记录存在于您的数据库中，并且没有 WHERE/JOIN 条件将它们切断吗？

标签： mysql sql group-by group-concat

【解决方案1】：

你想要的语法是：

group_concat(distinct t.name separator ',') as Products

【讨论】：

它返回一行，它不给出所有产品。
在这种情况下，您的查询需要group by 语句。类似于group by orderid, ordername。

【解决方案2】：

我用这个改变了我的问题：

    SELECT op.OrderId,
    O.Number,    
    SUM(op.Price) Price,
    (SELECT CONCAT(A.Detail, ' ',C.Name, ' / ', Ci.Name) FROM kobiakinlar.Address AS A
                INNER JOIN County AS C ON C.CountyId = A.CountyId
                INNER JOIN City AS Ci ON C.CityId = Ci.CityId
                WHERE UserId = O.UserId) AS UserAddress,
   ( SELECT CASE WHEN O.Status =0 THEN 'Onay Bekliyor'  WHEN O.Status =1 THEN 'Onaylandı' WHEN O.Status = 2 THEN 'Reddedildi' END) Status,
    O.Creation,
    ( SELECT CASE WHEN O.IsDelivered =0 THEN 'Teslim Edilmedi' ELSE 'Teslim Edildi' END) IsDelivered,
    group_concat(P.Name) Product
FROM
    kobiakinlar.product P
        JOIN
    kobiakinlar.orderproduct op ON op.ProductId = P.productId
        JOIN
    kobiakinlar.order O ON O.orderId = op.OrderId
   JOIN 
kobiakinlar.address A ON A.addressId = O.AddressId
GROUP BY op.OrderId

【讨论】：