100 Days of SQL

sql

Day 14 – SQL IN Operator

In SQL, the IN operator is used to specify multiple values in a WHERE clause. The IN operator allows you to specify a list of values, and the WHERE clause will return any rows where the specified column matches any of the values in the list.

The basic syntax for using the IN operator is as follows:


SELECT column_name FROM table_name WHERE column_name IN (value1, value2, value3, ...);

Here, column_name is the name of the column you want to search, table_name is the name of the table containing the column, and value1, value2, value3, etc. are the values you want to search for.

For example, suppose you have a table called employees with columns employee_id, first_name, last_name, and department. If you want to find all employees who work in the “Sales” or “Marketing” departments, you would use the following SQL statement:


SELECT * FROM employees WHERE department IN ('Sales', 'Marketing');

This statement will return all rows from the employees table where the department column matches either “Sales” or “Marketing”.

The IN operator can also be used with a subquery to search for values in another table. For example, suppose you have a table called sales with columns product_id, product_name, and price, and you want to find all products with a price higher than the average price. You could use the following SQL statement:


SELECT product_name, price FROM sales WHERE price > (SELECT AVG(price) FROM sales);

This statement will return all rows from the sales table where the price column is higher than the average price of all products in the sales table.