Deleted items are not gone straight away.
Where is the Trash?
Click the bin icon at the bottom of the left sidebar. The Trash page says: "Deleted workbooks, tables and functions are kept for 30 days, then deleted permanently. Restore an item to edit it again."
What does the list show?
The columns are Name, Contents and Deleted (for example "about 8 hours ago"). Contents shows what kind of item it is, for example Function.
How do I get something back?
Click Restore on its row. The page says restoring lets you edit it again.
How do I delete something for good?
Click Delete permanently on its row. This cannot be undone.
Good to know
Items stay for 30 days, then they are deleted permanently.
Deleting a column or running a column can be undone from a table's history. See the article on table options and history.

