sort of, although I think this belongs in the PHP/MySQL forum.
I'm assuming: your 500MB .sql file is a dump of your database, right? If so, you need this file on your computer somewhere. The "basic" way of reading it into your database using the command line (DOS prompt or what ever it's called these days) with the command:
mysql -u db_user db_name -p < large_file.sql
Change the parameters accordingly.
This may or may not work depending on what's in the .sql file; if it doesn't contain table definitions, you may need to add these first.
You might also want to watch out for how much free space you have, that 500MB may expand somewhat once it's read into the DB.