PRAGMA YqlSelect = 'force';

WITH x (a) AS (SELECT 1)
SELECT * FROM x;

WITH x (a, b) AS (SELECT 1, '2')
SELECT * FROM x;

WITH x (a, b) AS (SELECT 1 AS a, '2' AS b)
SELECT * FROM x;

WITH x (a, b) AS (SELECT 1 AS b, '2' AS a)
SELECT * FROM x;

WITH x (a, b) AS (SELECT 1 AS c, '2' AS d)
SELECT * FROM x;

WITH x (a, b) AS (
    SELECT 1 AS a, '2' AS b
    UNION ALL
    SELECT 11 AS a, '22' AS b
)
SELECT * FROM x;

WITH x (a, b) AS (
    SELECT 1, '2'
    UNION ALL
    SELECT 11, '22'
)
SELECT * FROM x;