DataScience100Knock-S34

code:1.sql

with sums as

(

select customer_id, sum(amount) as sum_amount

from receipt

group by customer_id

)

select avg(sum_amount)

from sums

where customer_id not like 'Z%';

これでもいいはず

code:2.sql

%%sql

select cast(sum(amount) as float)/count(distinct(customer_id))

from receipt

where customer_id not like 'Z%';