Who Doesn't Report to Anyone?
HR at Kestrel Labs is redrawing the org chart and needs the starting points: the people who sit at the top of a reporting line and answer to nobody inside the company.
Reporting lines are recorded on the employee row itself. Each person's row points at the id of the person they report to. For the people at the top there is nobody to point at, so that slot holds NULL — SQL's marker for "no value was recorded here". NULL is not zero and not an empty string; it is the absence of an answer, and it does not behave like a normal value when you compare it.
employees — one row per employee. manager_id holds the id of that person's manager, or NULL.
| id | name | department_id | salary | hire_date | manager_id |
|---|---|---|---|---|---|
| 1 | Ava Chen | 1 | 145000 | 2021-03-14 | NULL |
| 2 | Ben Ortiz | 1 | 118000 | 2022-06-01 | 1 |
| 3 | Cara Novak | 1 | 121000 | 2023-01-10 | 1 |
| 4 | Deshawn Lee | 2 | 95000 | 2020-09-23 | NULL |
| 5 | Elin Kask | 2 | 88000 | 2022-11-05 | 4 |
| 6 | Farid Amiri | 3 | 76000 | 2023-04-18 | NULL |
| 7 | Grace Kim | 4 | 132000 | 2021-07-30 | NULL |
| 8 | Hugo Silva | 4 | 110000 | 2023-02-14 | 7 |
| 9 | Ines Duarte | 4 | 104000 | 2023-08-01 | 7 |
| 10 | Jonas Weber | 2 | 91000 | 2021-12-19 | 4 |
The table already exists in the database — there is nothing to create or load.
Task: Write a query returning a single column, name, listing every employee with no manager recorded, in alphabetical name sequence.
Example output — shape only, on invented names.
| name |
|---|
| Anton Reis |
| Rosa Kwan |
| Yusuf Bello |
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