SQL query to return names of customers who have made a purchase in last 30...

This problem asks for a SQL query that returns the names and total amounts spent by customers who have made a purchase in the last 30 days.

Problem

```Write a SQL query that returns the names of all customers who have made a purchase in the last 30 days, along with the total amount spent.
Input:
customer_id | name | purchase_date | amount
1 | John | 2020-01-01 | 20
2 | Jane | 2020-02-01 | 30
3 | Joe | 2020-03-01 | 40
Output:
customer_id | name | total_spent
1 | John | 20
2 | Jane | 30
3 | Joe | 40```

Solution

This solution is in SQL. Our A.I. can create solutions in multiple languages.
```SELECT customer_id, name, SUM(amount) AS total_spent
FROM customers
WHERE purchase_date >= DATE_SUB(CURDATE(), INTERVAL 30 DAY)
GROUP BY customer_id, name;

/*

The solution above is optimal because it uses the GROUP BY clause to group the results by customer_id and name, and the SUM() function to calculate the total amount spent by each customer.

*/```

A.I. Evaluation of the Solution

The solution above is optimal because it uses the GROUP BY clause to group the results by customer_id and name, and the SUM() function to calculate the total amount spent by each customer.

Evaluated at: 2022-11-06 01:15:38