In my use case, I had 200 database tables that had some rows in a old naming convention and some in a new standard.
I created a python script to merge these tables using the notebooks in dataiku, the issue came after the rows were merged within the table with the new name. I couldn't find a good way to do the cleanup of the old tables, in this case. Just run a Drop table command in the database.
The dataset.delete(drop = True) didn't work for me because these objects were import to dataiku as externally managed (the only way I know of via python).