It is simple enough if you don't care about permissions, etc..., which is true of my local test database.
mysql -uUSER -p -e "drop database YOUR_DB;"
mysql -uUSER -p -e "create database YOUR_DB;"
mysql -uUSER -p YOUR_DB < SQL_FILE.sql
And now you get a refreshed DB.
If you don't mind getting deeper, here is an alternative way to drop tables.