How can I perform this aggregate?

Question

I have crated two table one is customers and the other one is ord

select * from customers;

    id  Name    age     adress  salary
2   102 jpj     24      zzzz           


        

Answer 1

You need to group the data; for example:

select c.name,c.id,sum(o.amount) as amount
from CUSTOMERS c
inner join ord o on c.id=o.customer_id
group by c.id, c.name