獲取數據表格2個表格並對結果進行求和

Question

我有兩個表格，其中包含信息：ID，persona_id，total_amount 角色ID可以重複十次。所以，我讓所有的人一個ID TOTAL_AMOUNT與查詢：

select d.id as debt_id, p.name as persona, sum(d.total_amount) as total_amount 
from debt d 
    join persons p on d.persona_id = p.id group by p.name 

我想在一個查詢每個表中獲取數據，並做aritmethic propertys與TOTAL_AMOUNT列，並將其返回爲1個TABEL。

表1

id persons_id total_amount 
1 2   50 
2 3   100 
3 2   200 
4 5   300 
5 1   500 

表2

id persons_id total_amount 
1 2   25 
2 1   100 
3 5   50 
4 3   100 
5 4   300 

結果我想獲得與算術運算comined 2個表 - 總量柱（，+，/，*）。 Basicaly一個變化，以獲得最終結果的總量在形式上，我想爲不同的情況。

什麼，我基於JohnHC answear工作是：

select c.id, c.persona_id, c.total_amount - d.total_amount as new_total 

from (   select c.id , c.persona_id, sum(c.total_amount) as total_amount from credit c 
       join persons p on c.persona_id = p.id 
       group by p.name) c 
inner join ( select d.id, d.persona_id, sum(d.total_amount) as total_amount from debt d 
       join persons p on d.persona_id = p.id 
       group by p.name) d 

on c.persona_id = d.persona_id 
group by c.id, c.persona_id 

Answer 1

如果你想總，請嘗試：

select id, person_id, sum(total_amount) 
from 
(
select id, person_id, total_amount 
from table1 
union all 
select id, person_id, total_amount 
from table2 
) 
group by id, person_id 

如果你想要做其他的事情，嘗試：

select t1.id, t1.person_id, t1.total_amount [+ -/*] t2.total_amount as new_total 
from table1 t1 
inner join table2 t2 
on t1.id = t2.person_id 
group by t1.id, t1.person_id