Combining Tables with INNER JOIN

INNER JOIN combines rows from two tables based on a matching condition.

It only returns rows where there is a match in BOTH tables.

SELECT e.first_name, d.name AS department_name
FROM employees e
INNER JOIN departments d
ON e.department_id = d.id;

Key concepts:

• Use aliases (e, d) to shorten table names
• ON specifies the matching condition
• Only matching rows appear in results
• Employees without a department are excluded

INNER JOIN is the most common type of join in SQL.