Self Join Managers — Solution & ExplanationProblems / Self Join Managers / EditorialApproach

Alias the employees table twice: e for the employee side and m for the manager side.

LEFT JOIN e to m on e.manager_id = m.emp_id. The LEFT JOIN ensures employees with no manager (NULL manager_id) still appear.

Select e.name as employee_name and m.name as manager_name.

Key InsightSelf-joins are useful for hierarchical data. The same table serves both roles — the key is using different aliases and understanding which column points to which.Hints

A self-join is when you join a table to itself using different aliases.

Use LEFT JOIN so that employees without a manager (CEO) still appear.

The join condition connects e.manager_id to m.emp_id.

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