Add fct_order_items model

models/example/fct_order_items.sql

@@ -0,0 +1,38 @@
+{# 
+create a fct_order_items table joining orders to order items. 
+select all fields from order items and join in the order_date, 
+email and customer_id from the orders table
+#}
+with orderitems as (
+
+    select * from {{ ref('order_items_upload') }}
+
+),
+
+orders as (
+
+    select * from {{ ref('orders_upload') }}
+
+),
+
+final as (
+
+    select
+        orderitems.id as order_item_id,
+        orderitems.order_id,
+        orderitems.price,
+        orderitems.quantity,
+        orderitems.size,
+        orderitems.color,
+        orderitems.product_id,
+        orders.created_at,
+        orders.email,
+        orders.customer_id
+
+    from orderitems
+
+    inner join orders on orderitems.order_id = orders.id
+
+)
+
+select * from final

models/example/order_calculations.sql

@@ -0,0 +1,29 @@
+with orders as (
+
+    select * from {{ ref('stg_orders') }}
+
+),
+
+orderitems as (
+
+    select * from {{ ref('stg_order_items') }}
+),
+
+calc as (
+
+    select 
+        orders.customer_id, 
+        lag(orders.created_at, 1) [ignore nulls] 
+        over (partition by orders.customer_id
+              order by orders.created_at desc) as created_at_prev,
+        created_at
+    from orders
+),
+
+final as (
+    select 
+        datediff(month, created_at, created_at_prev) as months_since_prior_order
+    from calc
+)
+
+select * from final