hi folks, Is it possible to do `Backward incompatible schema`update (like change data type) on OFFLINE table without downtime?

No. Applying backward incompatible schema change means it could cause problem when merging results from multiple segments (think of selecting a column which has inconsistent data type across segments), which is not allowed. In order to apply backward incompatible schema change, you need to create a new table and re-bootstrap the data.

ok thanks