mysql - 如何获取通过加入返回的多个帐户的金额总和

Question

我有 3 个表，例如:

所有者详细信息:-

 owner_id   owner_name
    ---------------------
    1            A
    2            B    
    3            C
    -------------------

车辆所有者:-

    v_id  vehicle_id   owner_id
    -------------------------
    1      1            1
    2      2            2
    3      4            1
    4      3            1 
    5      5            3 

交易:-

id   v_id         amount   transaction_type
--------------------------------
1      1           100       0
2      2           250       1
3      1           150       1
4      3           450       1
5      1           200       0
6      4           300       1
7      5           150       0
8      5           200       1

transaction_type= 0 然后 (-) transaction_type=1 然后 (+)

车主 A (1) 在表 vehicle_owner 中有 3 辆带有 v_id (1,3,4) 的车辆。

v_id (1,3,4) 在表 transaction (1,3,4,5,6) 中有 5 个条目金额总和600(-100+150+450-200+300)

现在我想要这样的列表:-.

owner_id   owner_name  amount
    ---------------------
    1            A       600
    2            B       250
    3            C       50
    -------------------

Answer 1

您可以使用以下查询:

SELECT od.owner_id, od.owner_name, SUM(t.amount) AS amount 
FROM owner_details od INNER JOIN vehicle_owner vo ON od.owner_id = vo.owner_id 
    INNER JOIN `transaction` t ON vo.v_id = t.v_id 
GROUP BY od.owner_id

<小时/>

如果您想使用额外的transaction_type，您可以使用以下内容:

SELECT od.owner_id, od.owner_name, SUM(CASE WHEN t.transaction_type = 0 THEN t.amount * -1 ELSE t.amount END) AS amount 
FROM owner_details od INNER JOIN vehicle_owner vo ON od.owner_id = vo.owner_id 
    INNER JOIN `transaction` t ON vo.v_id = t.v_id 
GROUP BY od.owner_id

demo: http://sqlfiddle.com/#!9/c5f8d/1/1