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WITH yourTable AS (
SELECT 'Jill' AS Name, NULL AS ReportsTo, 'manager' AS Position UNION ALL
SELECT 'Nathan', 'Jill', 'junior'
)
SELECT t1.Name, t1.ReportsTo, t1.Position, COALESCE(t2.Position, 'none') AS Boss
FROM yourTable t1
LEFT JOIN yourTable t2
ON t2.Name = t1.ReportsTo;
| Name | ReportsTo | Position | Boss |
|---|---|---|---|
| Jill | null | manager | none |
| Nathan | Jill | junior | manager |