https://ivanluminaria.com/en/tags/scd/Recent content in Scd on Ivan LuminariaHugoenTue, 11 Nov 2025 08:03:00 +0100https://ivanluminaria.com/en/posts/data-warehouse/scd-tipo-2/Tue, 11 Nov 2025 08:03:00 +0100https://ivanluminaria.com/en/posts/data-warehouse/scd-tipo-2/<p>The sales director shows up at the Monday morning meeting with a simple question: &ldquo;How many customers did we have in the North region last June?&rdquo;</p> <p>The DWH&rsquo;s answer: silence.</p> <p>Not because the system was down, or the table was missing. The data was there, technically. But it was wrong. The DWH returned the customers currently in the North region — not the ones that were there in June. Because every night, the loading process overwrote the customer master data with current values, erasing any trace of what came before.</p>