MySQL多重和表

Question

從下面的小提琴http://sqlfiddle.com/#!2/8f1d2/5我想總結交叉表作為下面的查詢，但是我遇到了sale_event的重復值的麻煩。 你有什么想法嗎

SELECT
 a.province_id,
 SUM(a.sale_event) AS sale_eventTotal,
 SUM(d.order_fullpay) AS order_fullpayTotal
FROM
    san_activites a
LEFT JOIN
    sale_event_detail d
ON
    a.san_activity_id = d.san_activity_id
WHERE 
    a.entry_date BETWEEN '2014-7-1' AND '2014-7-30'
GROUP BY a.province_id

Answer 1

只需刪除GROUP BY a.province_id並運行對我GROUP BY a.province_id的查詢即可。

Answer 2

在san_activity_id上添加唯一索引 ，或在查詢時進行重復數據刪除：

SELECT 
 SUM(a.sale_event) AS sale_eventTotal,
 SUM(d.order_fullpay) AS order_fullpayTotal
FROM
    san_activites a
LEFT JOIN
    (select * from sale_event_detail group by san_activity_id) d
ON
    a.san_activity_id = d.san_activity_id
WHERE 
    a.entry_date BETWEEN '2014-7-1' AND '2014-7-30'
GROUP BY a.province_id

小提琴

Answer 3

我能夠在下面獲得我認為您想要的結果。 結果帶回來
3 | 10
4 | 20

SELECT 
 SUM(a.sale_event) AS sale_eventTotal,
 SUM(d.order_fullpayTotal) AS order_fullpayTotal
FROM
    san_activites a
LEFT JOIN
    (select SUM(order_fullpay) AS order_fullpayTotal, san_activity_id from sale_event_detail group by san_activity_id) d
ON
    a.san_activity_id = d.san_activity_id
WHERE 
    a.entry_date BETWEEN '2014-7-1' AND '2014-7-30'
GROUP BY a.province_id

小提琴