Honestly, this is about the most boring feature in our entire product, but if you use SQL templates, and your data source is a little bit slow, it makes all the difference, so we decided it deserves its own changelog entry to show that even the most boring things can make the biggest difference.
The feature is opt-in, so if you have strict data handling requirements, you can keep it disabled to maintain absolute zero copy data handling. However, if you don't have any special data handling policies, go ahead and enable it by going to the data source settings, and clicking "Cache Settings" in the corner.