子查詢中的聚合

Question

我正在擺弄創建子查詢以適應它們。如果某個人的ID出現在聯結表X次數中，我試圖獲得ID號和相關費用。我試過

select id, charges from myTable 
where id in 
(
    select id from jxnTable 
having (count(jxn.id> 10)) 
group by jxn.id 

這給我的錯誤jxn.id is invalid in the select list because it is not contained in either an aggregate function of a group by clause.

Answer 1

誤區三：

• 的GROUP BY和HAVING必須是相同查詢的一部分，GROUP BY必須在相應的HAVING之前以文本方式出現。
• COUNT表達式附近的括號不正確。
• 您沒有名爲jxn的表格或別名。

試試這個：

SELECT id, charges 
FROM myTable 
WHERE id IN 
(
    SELECT id 
    FROM jxnTable 
    GROUP BY id 
    HAVING COUNT(id) > 10 
) 

Answer 2

你GROUP BY所屬的子查詢中，除了一些奇怪的()在HAVING條款。

select id, charges from myTable 
where id in 
(
    select id from jxnTable 
    GROUP BY id 
    having (count(id>) 10) 
) 

這也可以用一個JOIN得罪一個子查詢，而不是IN()條款，這可能會更快：

SELECT m.id, charges 
FROM myTable M 
    INNER JOIN (
    SELECT id FROM jxnTable 
    GROUP BY id 
    HAVING COUNT(id) > 10 
) cnt ON m.id = cnt.id