Vol. I · A Postgres HandbookTwelve chapters · · 756 queries

The Query & the Schema

A reading-room reference for writing PostgreSQL by hand — selects to window functions, with the schema in plain view.

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Chapters · WHERE & Filtering · Query 006 / 030
EasyWHERE & Filtering

Find employees with no manager (top-level)

The query

SQL
SELECT emp_id, first_name, last_name, job_title
FROM employees
WHERE manager_id IS NULL;
Tested against PostgreSQL 16

Note

“IS NULL finds rows where the value is absent. These are likely CEOs/VPs.

Tables referenced

  • employees10 cols

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The Query & the Schema

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Compiled for Postgres 16 · MMXXVI