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SQL: Manager of Manager

MediumSQL · PostgreSQL00:00
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Your question is SQL: Manager of Manager. Start with the requirements and the one table on the right.

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Problem

Business Context

Walmart Global Tech maintains an employee hierarchy for organizational reporting. The reporting team needs to display each employee's direct manager and second-level manager, including employees whose hierarchy is incomplete.

Task

Write a PostgreSQL query that returns every employee, their direct manager, and their manager's manager.

Requirements

  1. Use self-joins on the employees table to resolve both management levels.
  2. Preserve employees with no manager or with an unmatched manager record, showing NULL for unavailable names.
  3. Return one row per employee, ordered by employee_id ascending.

Schema

employees
ColumnTypeDescription
employee_idPKINTUnique employee identifier
manager_idINTSelf-referencing employee ID for the direct manager
employee_nameVARCHAR(100)Employee's full name
Tablesemployees
Your solutionPostgreSQL
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