[Dovecot] Using MySQL to store email?

[Joshua Goodall]

Marc Perkel: 
> Suppose I want to move all message from a specific host to another
folder.
> UPDATE table SET folder=new-folder WHERE host=value;
> 
> With databases you can do things you would have to write complex
programs
> to do with files. Things that you would consider to be impossible are
> trivial with databases.
>
> This outside the box.

People who optimise their systems for shiny cute features rather than
the common case get all the hacks they deserve.

Repeat after me: design for the common case.

Also your proposed sql above and implications (arbitrary operations
based on mail metadata i.e. headers) seems to involve indexing every
mail header on delivery.  Good luck with that one large scale mail
storage.  Did you want a mail database, or an OLAP system? >-)

/jg