[Solved] Given tables employees and departments with columns employees.dept_id and departments.id, what will this query return?SELECT e.name, d.name FROM employees e LEFT JOIN departments d ON e.dept_id = d.... | SQL

SQL - Advanced Joins

Given tables employees and departments with columns employees.dept_id and departments.id, what will this query return?

SELECT e.name, d.name FROM employees e LEFT JOIN departments d ON e.dept_id = d.id WHERE d.name IS NULL;

AAll employees and all departments

BEmployees who belong to a department

CEmployees without a matching department

DDepartments without employees

Step-by-Step Solution

Solution:

Step 1: Understand LEFT JOIN with WHERE condition
LEFT JOIN keeps all employees; WHERE d.name IS NULL filters those without matching department.
Step 2: Interpret the result
Only employees whose dept_id does not match any department id will appear.
Final Answer:
Employees without a matching department -> Option C
Quick Check:
LEFT JOIN + WHERE NULL on right = unmatched left rows [OK]

Quick Trick: WHERE NULL on joined table filters unmatched rows [OK]

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Given tables employees and departments with columns employees.dept_id and departments.id, what will this query return?