Editing Extract, transform, load (section)

=== Virtual ETL ===

{{Unreferenced section|date=September 2024}}

[[Data virtualization]] can be used to advance ETL processing. The application of data virtualization to ETL allowed solving the most common ETL tasks of [[data migration]] and application integration for multiple dispersed data sources. Virtual ETL operates with the abstracted representation of the objects or entities gathered from the variety of relational, semi-structured, and [[unstructured data]] sources. ETL tools can leverage object-oriented modeling and work with entities' representations persistently stored in a centrally located [[hub-and-spoke]] architecture. Such a collection that contains representations of the entities or objects gathered from the data sources for ETL processing is called a metadata repository and it can reside in memory or be made persistent. By using a persistent metadata repository, ETL tools can transition from one-time projects to persistent middleware, performing data harmonization and [[data profiling]] consistently and in near-real time.