while comparing the features available in different SQL server editions, i see that Fast recovery and Accelerated Database recovery are 2 separate features. I am unable to find any documentation specific for Fast recovery, and other online blogs seem to use both features interchangeably. Does anyone know how exactly are they different? The screenshot is captured from Editions and supported features of SQL Server 2019 (15.x)
Here's the excerpt from the Recovery and the transaction log documentation that describes the Fast recovery feature:
To maximize the availability of databases in an enterpirse environment, SQL Server Enterprise Edition can bring a database online after the Redo Phase, while the Undo Phase is still executing. This is known as Fast Recovery.
Fast recovery is an old feature and is related to how an Enterprise server will allow a database to be accessible after a crash, once the redo phase has been completed on the database. https://www.sqlskills.com/blogs/paul/fast-recovery-used/
Accelerated database recovery is a new 2019 feature which allows the database to be online much quicker even when there is a significant undo phase to be completed. This is available in Standard Edition so, fast recovery wouldn't be available here and so it's a useful feature.