3번SELECT u.user_id, u.email, COALESCE(p.point,0) 'point' FROM users u JOIN point_users p ON u.user_id = p.user_id order by p.point desc; 4번SELECT c.CustomerName, COUNT(o.OrderID) AS OrderCount, SUM(o.TotalAmount) AS TotalSpent FROM Customer c JOIN Orders o ON c.CustomerID = o.CustomerID GROUP BY c.CustomerID, c.CustomerName HAVING (SELECT COUNT(*) ..