In your recovery practice we often face the problem when data lost by execution DROP TABLE or DROP DATABASE statement. In this case even our InnoDB Data Recovery tool can’t help, as table / directory with files was deleted (if you have innodb-file-per-table). And the same for MyISAM, all .MYD / .MYI / .frm – files are deleted in this case.
So first step after DROP is to restore files, and for ext3 file system there are two utilities which can help of you are fast (and lucky) enough.
First one is ext3grep http://code.google.com/p/ext3grep/, with some instruction on this page http://www.xs4all.nl/~carlo17/howto/undelete_ext3.html.
And also there is TestDisk, with wide list of functionality, one of them is to restore deleted files.
I don’t know such tools for xfs, so in this case DROP will be fatal.
But better advise is do your backups 🙂