如何用不同的分組標準求和多個列

Question

當前我在做一個項目，我需要生成從表中提取的報表。 表按如下

CURRENCY_A AMOUNT_A CURRENCY_B AMOUNT_B CURRENCY_C AMOUNT_C

我的預期是由貨幣 USD（AMOUNT_A + AMOUNT_B + AMOUNT_C）基團的總計總和：
EURO：
磅數：

是否有可能單獨在oracle中執行此輸出？

Answer 1

SELECT currency, SUM(total1) AS total FROM 
(
SELECT currency_a AS currency, SUM(a_amount) AS total1 FROM table1 
GROUP BY currency_a 
UNION ALL 
SELECT currency_b, SUM(b_amount) AS total2 FROM table1 
GROUP BY currency_b 
UNION ALL 
SELECT currency_c, SUM(c_amount) AS total2 FROM table1 
GROUP BY currency_c 
) T 
GROUP BY currency