Warehouse-Ebenen:
RAW → STAGING → CORE → MARTS
Frühe IDs: shop_id, product_id, sku, customer_id, order_id, order_item_id, page_id/URL, session_id, event_id, campaign_id, experiment_id.
shop_id
product_id
sku
customer_id
order_id
order_item_id
page_id
session_id
event_id
campaign_id
experiment_id