I have a database which I have backed up . Now i am trying to delete all the content from the original db and restore it to it\'s empty state. since it\'s a relational db it
You could temporarily drop or disable all constraints, truncate all tables, and then restore the constraints. I've taken this approach for SQL Server and it works fine.
http://lists.mysql.com/mysql/194954
Perhaps an even better approach would be to reverse out the schema into scripts (which you put under version control) and then recreate the database from scratch.