You can use Bigdump to import larger sql bckups. I used a couple of times to restore large phpBB DBs. It's really handy, you just have to set your DB setting (user, passwd, etc), upload the script, your sql file and go!
The limit for uploading the sql directly from the browser is set by your php.ini (default for DH is 7meg) but you can also FTP it.
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