An offline table means nobody other than the job that moved it to or created it in the offline state is supposed to interact with it; doing so violates the assumptions that job makes about its exclusive interactions with that table, in particular safety of non-transactional and non-lease-holding interactions.

However currently it appears that DROP ... CASCADE is cascading to offline tables, violating this invariant.

To reproduce:

• Start a job that creates or moves a table into OFFLINE. (e.g. RESTORE db.tbl)
• While that job is running or paused, drop the database containing that table with cascade (DROP DATABASE db CASCADE).
• Observe that the job is still running but the table is now in DROP and its namespace entry has been removed.

Jira issue: CRDB-17485