I have over 15 years of ETL experience on "real world" projects & am now teaching grad courses in the Business Intelligence life cycle.  It does not make any sense to separate the ETL process into "layers". I do recommend that "all" tables do show in a star schema diagram so…

@Jay Allen  Jay, Look again at sources for your own understanding. My understanding of top down data warehouse for an enterprise has an origin that has been trusted for decades. "Subject-oriented, non-volatile, integrated..." (crediting Bill Inmon). As a practitioner, I do…

A definition of a data warehouse was been for years anchored in retaining data that is no longer changing. A B2B e-commerce environment includes many dynamics of data while being volatile, with factors that influence the frequency of queries and updates. eCommerce is…