如何總結M1和M2在此查詢

Question

我對結果表明 查詢現在，我需要和M1，M2

查詢：

select metraj, fee, tedad, fee_tedad, 
     metraj * fee AS m1, 
     tedad * fee_tedad AS m2 
from content 
where id = 54 

Answer 1

做這樣

select metraj, fee, tedad, fee_tedad, 
     metraj * fee AS m1, 
     tedad * fee_tedad AS m2, 
     metraj * fee+tedad * fee_tedad as sum 
from content 
where id = 54 

Answer 2

select metraj, fee, tedad, fee_tedad, metraj * fee AS m1, tedad * fee_tedad AS m2, mtraj * fee + tedad * fee_tedad as m1_plus_m2 from content where id = 54 

Answer 3

以下應該工作：

select metraj, fee, tedad, fee_tedad, (metraj * fee) + (tedad * fee_tedad) AS someVariable, from content where id = 54 

如果你需要同時M1也m2的然後使用以下命令：

select metraj, fee, tedad, fee_tedad, metraj * fee AS m1, tedad *fee_tedad AS m2, (metraj * fee) + (tedad * fee_tedad) AS someVariable from content where id = 54