SQL「分裂」基團通過

Question

我有以下表：

('cat', 5000, 7000, 'A'), 
('dog', 9200, 11000, 'A'), 
('fog', 6500, 9300, 'B'), 
('fox', 16001, 15001, 'B'), 
('cat', 5005, 7005, 'B'), 
('dog', 9299, 11399, 'B'), 
('cat', 5005, 7005, 'B'), 
('dog', 9299, 11399, 'B'), 
('fox', 16001, 15002, 'A') 

我需要通過第一列，以獲得選擇groub然後4列與的總和：

COL2爲一個標誌，

COL3爲一個標誌，

COL2爲B標誌和

COL3對於B˚F落後。

我怎樣才能得到這個？

SQLFiddle

Answer 1

SELECT 
    Animal, 
    SUM(CASE WHEN flg = 'A' THEN V1 ELSE 0 END) AS A_V1, 
    SUM(CASE WHEN flg = 'A' THEN V2 ELSE 0 END) AS A_V2, 
    SUM(CASE WHEN flg = 'B' THEN V1 ELSE 0 END) AS B_V1, 
    SUM(CASE WHEN flg = 'B' THEN V2 ELSE 0 END) AS B_V2 
FROM 
    MyTab 
GROUP BY 
    Animal 

Answer 2

select animal, 
    SUM(If(flg='A',V1,0)), 
    SUM(If(flg='A',V2,0)), 
    SUM(If(flg='B',V1,0)), 
    SUM(If(flg='B',V2,0)) 
from MyTab 
group by animal