Why mysqlimport restore "*.sql" file failes?

[Micheal Jonson]

Hi, all:
Here I sufferred an error when I used mysqlimport command to restore my backup file, under windows system.
I entered the commands in window shell like this:
"C:\> mysqlimport -ulogin -ppassword -l my_db my_file.sql"
But the shell threw out an error as followed:
"mysqlimport: Error: Table 'my_db.my_file' doesn't exist"
The pre-restored file was just under the right directon. The error was perplexed to me. So could someone be generous to reply this?
Thanks a lot.