SQL processing values of user defined columns

I can do that:

SELECT
   1 AS one,
   2 AS two,
   1 + 2 AS three;

开发者_StackOverflow社区But I would like to do that:

SELECT
    1 AS one,
    2 AS two,
one + two AS three;

Is it possible?

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You can do this:

SELECT one, two, (one+two) as three
FROM 
(
    SELECT 
         1 AS one 
         2 AS two
) t;

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A way is this:

SELECT one, two, one + two AS 'three'
FROM (SELECT 1 as 'one', 2 as 'two') myTable