SQL · Pattern 6 — Joins
Non-Equi Join
A non-equi join uses comparison operators such as BETWEEN, < or > instead of equality.
Source data — Pattern 6: Joins
All queries run against the shared employees and departments tables (see schema.sql). This pattern introduces the departments table. Topic 38 also needs a projects table, while topic 39 introduces a salary_grades table for non-equi joins.
What it does
A non-equi join uses comparison operators such as BETWEEN, < or > instead of equality.
Problem
Find salary grades using salary ranges.
SELECT e.first_name,
s.grade
FROM employees e
JOIN salary_grades s
ON e.salary BETWEEN s.min_salary AND s.max_salary;
Result
