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WITH yourTable AS (
SELECT 'A' AS id, 12 AS val UNION ALL
SELECT 'B', 14 UNION ALL
SELECT 'C', 20 UNION ALL
SELECT 'D', 78 UNION ALL
SELECT 'E', 90 UNION ALL
SELECT 'F', 65
),
cte AS (
SELECT *, (ROW_NUMBER() OVER (ORDER BY id) - 1) % 2 rem
FROM yourTable
)
SELECT id, val
FROM cte
WHERE rem = 0;
| id | val |
|---|---|
| A | 12 |
| C | 20 |
| E | 90 |