In financial services, the questions that matter most are rarely answered by “the latest record.”
Regulators, auditors, model validators, and operations teams want something more specific: what was true for the business at the time, and what did we know at the time? That’s bitemporal thinking—and it’s exactly the kind of problem where Microsoft Fabric’s Lakehouse on Delta becomes more than storage. It becomes a practical design advantage.
In this post, I’m going to walk through what bitemporal tables actually require, why intervals matter (ValidFrom/ValidTo), and how to implement bitemporal efficiently in Fabric by leaning into #DeltaLake in the Lakehouse. We’ll ground it with two #FSI examples (low velocity KYC and high velocity trades/payments), and we’ll add a derived-layer option using materialized lake views to calculate closure dates. Finally, we’ll cover when Azure SQL Database (including Hyperscale) is the right operational complement to Fabric.
