Anyone ever consider a filesystem served by MySQL for mail folders?

[Doug Lee]

Ok, tell me if this is a totally awful idea, but it seems quite useful
to me, even if unusual...

Is it practical to implement a mountable filesystem for mail archiving
whose contents are served by a MySQL (or other SQL) database?
Creating this is surely way beyond my level of expertise in FreeBSD,
and maybe even the full design is, but I imagine this much:

The actual supporting database would include category strings for each
message (many-to-many).  File names in the filesystem would be
category strings, so saving an email would file it in that category
(to save in several categories, resave to the corresponding names;
only one actual copy of the message would be saved).

Special rules could be constructed that allow special filename formats
to cause queries; for example, trying to load messages from a file
called "from:dgl@%" might pull in a mail file consisting of all
messages from dgl@* (note I use `%', the SQL wildcard, both to
simplify the query and to avoid collision with the normal `*' wildcard
for filenames).  I suggest the rule<-->filename mapping should be held
in an administrator-modifiable configuration file.

The reason I propose all this is that I'm interested in a better way
to store massive amounts of email that does not depend on a particular
mail program.  Granted, the returned mail file format would have to be
preset--unless that's configurable too, or special patterns are
included for different formats compatible with different mailers,
which would be immensely cool!

I am continually frustrated by trying to find an email among hundreds
of thousands of them, and by the inability to categorize emails in
multiple ways easily without saving multiple copies of messages.  I
suddenly today thought of things like devfs, procfs, etc., that are
pseudo-filesystems, and realized that even if this is an odd approach,
it does have the benefit (at least potentially) of working with most
any mail client with no modification to the client and no user
intervention such as manually copying messages to/from the database.
If such a thing now existed that could serve Mutt-compatible (MMDF, I
think) mail files, I would wish to import about 400 megabytes of
messages as soon as possible. :-)

Thoughts welcome.  Please Cc me.


-- 
Doug Lee           dgl at dlee.org        http://www.dlee.org
BART Group         doug at bartsite.com   http://www.bartsite.com
"Innovation is hard to schedule." -- Dan Fylstra