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CREATE TABLE customer(customer_id int ,first_name varchar(100) ,last_name varchar(100))
CREATE TABLE payment (customer_id int , amount decimal(10,2))
SELECT CONCAT (c.first_name, ' ', c.last_name) as customer
FROM customer c INNER JOIN payment p ON c.customer_id=p.customer_id
GROUP BY c.customer_id , CONCAT (c.first_name, ' ', c.last_name)
ORDER BY SUM(CAST(p.amount as float)) desc
LIMIT 1;
| customer |
|---|