Where does MPNews store messages?
With MPNews, you can choose whether to store messages as individual files on disk,
or in any standard SQL database such as Microsoft SQL Server or MySQL.
By storing messages on disk, you get a very high performance system that is also
very easy to back up and move between servers. However, if you want to be able to
reuse your newsgroup messages in other systems or easily gather statistics on how
your newsgroups are being used, you can choose to use an SQL database to store your
messages.