Three data marts, three truths about sales: the bus matrix as common ground
Kimball bus matrix to align isolated data marts: conformed dimensions, business processes and comparable sales. Real insurance group case.
Kimball
3 tagged articles
Data Warehouse
Data Warehouse
SCD Type 2: the history the business didn't know it needed
SCD Type 2 in the data warehouse: historicising dimensions with surrogate keys and validity dates. Real case: a customer dimension that evolves over time.
Data Warehouse
Wrong grain: when the fact table can't answer the right questions
Data warehouse: fact table grain determines which questions you can answer. Common mistakes in granularity and their impact on the dimensional model.