Answer
A join combines rows from two table expressions according to a join condition. • An inner join keeps matching row combinations. • Outer joins can also preserve unmatched rows from one or both sides. • A correct join condition prevents accidental Cartesian products.
💡 SQL Example
SELECT e.name, d.name AS department FROM employees e JOIN departments d ON d.department_id = e.department_id;
Result
Maya | Engineering
⚡ Quick Revision
A join combines related rows using an explicit condition.