183. Customers Who Never Order

https://leetcode.com/problems/customers-who-never-order

Pandas

import pandas as pd


def find_customers(customers: pd.DataFrame, orders: pd.DataFrame) -> pd.DataFrame:
    result = pd.DataFrame()
    result['Customers'] =  customers[~customers.id.isin(
        orders.customerId
    )]['name']
    return result

SQL

SELECT
    Customers.name AS Customers
FROM Customers
WHERE id NOT IN (
    SELECT DISTINCT customerId
    FROM Orders
)