cDEM: Extract Core Data Elements for Migration Accelerating from Legacy Platform to Modern Cloud Environment

Data migration from legacy systems to modern environments, such as migrating DB2 from z/OS to the cloud, often requires significant effort and time. Customers often encounter confusion when determining the appropriate migration route, use case, and efficient movement of source data to the target data repository. This paper explores various migration patterns and provides recommendations on target technology and platform selection. We propose a core Data Elements Migration (cDEM) strategy, focusing on schema, objects, and data volume, rather than a complete data warehouse. By enabling users to quickly assess workload, extract core data elements, map components from the source data pool to the target repository, and evaluate data volume and migration complexity, this approach reduces workload and accelerates the overall process. The model presented in this paper illustrates the migration of end-to-end data objects from legacy DB2 on z/OS to the public cloud, specifically Azure SQL Server as a demonstration case, while remaining applicable to other cloud providers and popular data repositories like MySQL.