DZone

If you’ve made it to this blog you’ve probably heard the term “persistent” thrown around with ETL, and are curious about what they really mean together. Extract, Transform, Load (ETL) is the generic concept of taking data from one or more systems and placing it in another system, often in a different format. Persistence is just a fancy word for storing data. Simply put, persistent ETL is adding a storage mechanism to an ETL process. That pretty much covers the what, but the why is much more interesting… 

ETL processes have been around forever. They are a necessity for organizations that want to view data across multiple systems. This is all well and good, but what happens if that ETL process gets out of sync? What happens when the ETL process crashes? What about when one of the end systems updates? These are all very real possibilities when working with data storage and retrieval systems. Adding persistence to these processes can help ease or remove many of these concerns. 

Source: DZone