How to Use IN in SQL

The IN operator allows you to specify multiple values in a WHERE clause. It checks if a value matches any value in a list or subquery.

Syntax:

SELECT columnsFROM table_nameWHERE column_name IN (value1, value2, value3, ...);

Or with a subquery:

SELECT columnsFROM table_nameWHERE column_name IN (    SELECT column_name FROM other_table WHERE condition);

Example 1: Using IN with a list of values

Find employees who work in either 'Sales', 'Marketing', or 'IT' departments:

SELECT *FROM employeesWHERE department IN ('Sales', 'Marketing', 'IT');

Example 2: Using IN with a subquery

Find employees who belong to departments that have more than 10 employees:

SELECT *FROM employeesWHERE department_id IN (    SELECT department_id    FROM employees    GROUP BY department_id    HAVING COUNT(*) > 10);

Notes:

• IN is equivalent to multiple OR conditions (e.g., WHERE dept = 'Sales' OR dept = 'Marketing').

• You can use NOT IN to exclude values.

• IN works with numbers, strings, and dates.

If you want, I can help you write IN queries for your specific data!