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Identify who is a manager and who is not.

General/Othereasy0.4 min readPremium
Frequency
Low
Asked at 1 company
Category
243
questions in General/Other
Difficulty Split
151E|43M|49H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
HashedIn
Key Concepts Tested
sql
Expert AnswerPremium
79 wordsInterview-ready
Manager = employee who is parent_id for at least one other. SQL: SELECT e.id, e.name, CASE WHEN EXISTS (SELECT 1 FROM employees e2 WHERE e2.manager_id = e.id) THEN 'Manager' ELSE 'Non-Manager' END AS role FROM employees e. WHY: EXISTS is efficient—short-circuits; avoids duplicate scans. Handle NULL manager_id (CEO). SCALABILITY: Index on manager_id; for large orgs, consider materialized view or closure table for hierarchy queries....
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