Automatic type widening in Auto Loader
Evolves an integer column to long, or float to double, without rewriting the table.
Why it is worth watching
Schema evolution is the part of Auto Loader people get wrong most often, and this changes the answer.
What Public Preview promises
Open to everyone and supported for production use, though it can still change. On by default, and an admin can turn it off.
| Who can use it | Everyone |
|---|---|
| Production use | Yes |
| Support | The support team |
| On by default | Yes, with an opt-out |
The definitions are Databricks' own, on its release types page. The label on this page is the one the feature's documentation states, last checked on 13 Sept 2026.
Where to read more
We have not written a concept about it yet: while it is in preview the documentation is the place to read, and it moves faster than a page here would.
The Databricks documentation for Automatic type widening in Auto Loader