Add a test

Author: victorcouste

tests/assert_total_payment_amount_is_positive.sql

@@ -0,0 +1,8 @@
+-- Refunds have a negative amount, so the total amount should always be >= 0.
+-- Therefore return records where this isn't true to make the test fail
+select
+    order_id,
+    sum(amount_usd) as total_amount
+from {{ ref('stg_payments' )}}
+group by 1
+having not(sum(amount_usd) >= 0)