The value n may be 1 or 0:
When 1 (true) a DROP TABLE statement deletes the table and the table's data.
When 0 (false) it deletes the table, but does not delete the data.
0 or 1. The default is 1.
On the page System Administration > Configuration > SQL and Object Settings > General SQL Settings, for the Does DDL DROP TABLE Delete the Table's Data setting, choose Yes (true) or No (false).