求一SQL语句

Question

现在有一表，字段(id,number1,number2,number3,number4,number5) number都是double型
现在我想查出每行记录的number1,number2,number3,number4,number5的和
如何实现

Answer 1

select number1+number2+number3+number4+number5 from tab

Answer 2

select id,number1,number2,number3,number4,number5,
number1+number2+number3+number4+number5 sum_col
from tab

Answer 3

为什么强调是double呢？
select id,number1,number2,number3,number4,number5,number1+number2+number3+number4+number5 total from table1

Answer 4

select id,
number1+number2+number3+number4+number5 sumnum5
from tb

Answer 5

select number1+number2+number3+number4 from tab
这样就行啦？