from invoices
derive total = case [total < 10 => total * 2, true => total]
select { customer_id, invoice_id, total }
take 5
append (
from invoice_items
derive unit_price = case [unit_price < 1 => unit_price * 2, true => unit_price]
select { invoice_line_id, invoice_id, unit_price }
take 5
)
select { a = customer_id * 2, b = math.round 1 (invoice_id * total) }