SQL服务器：分组的原因“列无效”错误，如何解决？

Question

我想筛选cg_group名称（请查询）和组（使用：GROUP BY）根据最近更新的机会的结果（使用：ORDER BY opportunities.date_modified DESC）。

当我使用的查询，而无需使用GROUP BY返回的结果如下：

SELECT cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0' 
ORDER BY opportunities.date_modified DESC

结果：

ABC Group
ABC Group
CBC Group
ABC Group
XYZ Group

但我想这组顺序如下：

ABC Group
CBC Group
XYZ Group

要做到这一点，我添加GROUP BY cg_groups.name

SELECT cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0' 
GROUP BY cg_groups.name
ORDER BY opportunities.date_modified DESC

但现在我得到这个错误：

消息8127，级别16，状态1，行10 因为它不是在聚合函数或GROUP BY子句中包含列“opportunities.date_modified”是在ORDER BY子句无效。

有人请帮我解决这个问题，谢谢。

Answer 1

使用ROW_NUMBER找到每个组的最近更新的记录：

WITH cte AS (
    SELECT cg_groups.name, o.date_modified,
        ROW_NUMBER() OVER (PARTITION BY o.date_modified DESC) rn
    FROM cg_groups cg
    INNER JOIN cg_groups_cstm cgc
        ON cgc.id_c = cg.id
    INNER JOIN accounts_cstm ac
       ON cg.name = ac.client_group_c
    INNER JOIN accounts a
       ON a.id = ac.id_c
    INNER JOIN accounts_opportunities ao
        ON a.id = ao.account_id
    INNER JOIN opportunities o
        ON ao.opportunity_id = o.id
    WHERE cg.deleted = '0' AND cgc.status_c = '1' AND o.deleted = '0'
)

SELECT name
FROM cte
WHERE rn = 1
ORDER BY date_modified DESC;

请注意，这可能不是你想要什么。这个答案返回每名组是最近更新的该组的单个记录。然后，它令所有的结果下降，但也许你想上升。

Answer 2

把opportunities.date_modified在选择和group by，那么你可以通过使用，为了

SELECT opportunities.date_modified,cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0' 
GROUP BY cg_groups.name,opportunities.date_modified
ORDER BY opportunities.date_modified DESC

但你的结果，你可以尝试像下面只是使用不同

SELECT distinct cg_groups.name
FROM cg_groups
JOIN cg_groups_cstm ON cg_groups_cstm.id_c = cg_groups.id
JOIN accounts_cstm ON cg_groups.name = accounts_cstm.client_group_c
JOIN accounts ON accounts.id = accounts_cstm.id_c
JOIN accounts_opportunities ON accounts.id = accounts_opportunities.account_id
JOIN opportunities ON accounts_opportunities.opportunity_id = opportunities.id
WHERE cg_groups.deleted='0' AND cg_groups_cstm.status_c='1' AND opportunities.deleted='0'
order by cg_groups.name

没有组的需求，因为你还没有使用任何聚合函数

Answer 3

怎么样你distinct声明之后只是增加SELECT。

Select distinct ... from ...