[Solved] Identify the error in this SQL query intended to list employees with their managers:SELECT e.name, m.name FROM employees e JOIN employees m ON e.id = m.manager_id; | SQL

SQL - Advanced Joins

Identify the error in this SQL query intended to list employees with their managers:

SELECT e.name, m.name FROM employees e JOIN employees m ON e.id = m.manager_id;

AUsing JOIN instead of LEFT JOIN causes missing employees without managers.

BThe query is missing a WHERE clause to filter managers.

CThe join condition is reversed; it should be e.manager_id = m.id.

DThe SELECT clause should use aliases for columns.

Step-by-Step Solution

Solution:

Step 1: Analyze join condition
The query joins on e.id = m.manager_id, which means employee's id equals manager's manager_id, incorrect.
Step 2: Correct join condition
It should be e.manager_id = m.id to link employee to their manager.
Step 3: Effect of error
Current join will not correctly associate employees with their managers.
Final Answer:
The join condition is reversed; it should be e.manager_id = m.id. is correct.
Quick Check:
Employee.manager_id matches Manager.id [OK]

Quick Trick: Join on employee.manager_id = manager.id [OK]

Common Mistakes:

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