On Wed, 21 Jan 2026 23:28:46 -0800 Ron <[email protected]> wrote: > We're talking email *messages*, not files - there's no requirement > that messages are files.
You dropped the "arbitrary". When everything fits neatly into tables or key/value stores then sure, a database might work. Email messages are not neat. They are very much like medical records: arbitrary in size and structure. Few databases can deal well with this kind of data. You can read up on all of Oracle's failures in the EMR space, and the history of WinFS, at your own pace, as examples of this. SQL is not a database. It is a language for making queries of servers. The server doesn't need to be a database. It can be anything with an SQL binding. > "Find the one message out of 50,000 where the subject is $x" is going > to be faster in a DB. Every. Single. Time. (Searching on the server > is not uncommon.) I call straw man. Search? Sure, databases can be good for this if the (meta)data fit, and the *right* (meta)data are stored in the database. But only while the indices are resident. If the database has to go to disk to read index data then performance drops through the floor. For reading and writing arbitrary data, which is the majority of what mail servers do? Files are faster than database in most instances. > > It's brilliant in its simplicity. > But it's outdated in its implementation. This isn't the 90s anymore > (MailDir designed in 1995). SMTP is outdated in its implementation. This isn't the 1980s any more (SMTP designed in 1980). I call straw man again. > And, what other software changes filenames to indicate something has > happened with the file? GNU Emacs to name an easy one, depending on how you have versioning configured. The VMS filesystem does similar versioning. Microsoft Onedrive and Sharepoint do something similar to VMS though they mask it by moving files to the hidden trash directory. I expect the competition operate similarly. These are some low-hanging fruit. I'm sure you can find others with a little effort. > Oh, and backups - rsync sees all these changes in file names and wants > to back them all up again despite the contents unchanged. *snrk*. Some files that are a few 10s of KB each needing to be re-backed up is bad, but changing one flag in a 1TB database causing the ENTIRE 1TB to need to be backed up is good? And never mind the challenges with backing up live database files. I think this is a you problem, not a Maildir problem. rsync solved this long ago (read the manual, specifically the --fuzzy option). Block level diffs such as zfs snapshot send/receive and deduplicating backup systems such as Borg make it a non-problem. > I'm unclear on what that's supposed to mean, but since it's *not* MS > Exchange, it *does* support open standards, and it *is* open source > software, what's the problem? The problem is just what I said: databases are terrible tools for storing arbitrary files and data. They can be coerced into working, and they have benefits for certain activities, and sometimes they can be "simple" solutions to complicated problems, but overall they're just bad at it. -- \m/ (--) \m/ _______________________________________________ Discuss mailing list [email protected] https://lists.blu.org/mailman/listinfo/discuss
