Juliano F. Ravasi writes:
In my experience, there are many different ways to
export and import
data from and to MySQL databases, and many, many of them are broken when
it comes to binary data or non-ASCII text. Many hosting providers use
phpMyAdmin or some variant to export MySQL databases for backup. Do not
use that!
The secure way to backup databases and reimport them somewhere else is
to use the command-line tools.
To export:
mysqldump -uUSER -p DATABASE > FILENAME.sql
To import:
mysql -uUSER -p < FILENAME.sql
I also recommend checking that the terminal locale in both systems are
compatible with the 'locale' (Linux) or 'env' (other) commands. In the
case of doubt, add "LANG=C LC_ALL=C" before each command to force a
common locale in both systems.
That's not always secure for MediaWiki. See
http://www.mediawiki.org/wiki/Manual:Backup#Character_set