IN

IN (list) is shorthand for a chain of OR column = value checks against a fixed list — much easier to read (and write) than several ORs once the list grows past two or three values.

Source data — Pattern 2: Filtering Data

All queries run against the shared employees table (see schema.sql). This pattern also needs the manager_id column for topic 14 — not required back in Pattern 1. It also needs one row with salary < 50000 for topic 9, which Pattern 1's 6 rows didn't have — add:

INSERT INTO employees (employee_id, first_name, last_name, salary, department_id,
manager_id)
VALUES (7, 'Zoya', 'Khan', 42000, 500, 1);

IN — source table 1

What it does

IN (list) is shorthand for a chain of OR column = value checks against a fixed list — much easier to read (and write) than several ORs once the list grows past two or three values.

Problem

Find employees working in IT or HR.

SELECT *
FROM employees
WHERE department_id IN (100, 200);   -- 100 = IT, 200 = HR

Result

IN — result 1