On Wed, Mar 25, 2009 at 5:58 PM, David Pollak <[email protected]> wrote: > On Wed, Mar 25, 2009 at 9:46 AM, Darren Hague <[email protected]> wrote: > >> I think there's a distinction to be made here between mutable objects and >> mutable data - or are you saying that SQL UPDATE is inherently evil? ;-) >> >> To preserve object immutability, a copy of the message object with >> "deleted=true" could be created, and this could replace the previous message >> in people's mailboxes as a side-effect of the method which updates the >> message record in the database. Put another way, a mailbox which receives a >> "deleted=true" message would cause a matter/antimatter-like annihilation of >> the original message. > > > Knowing which mailboxes a particular message made it to, especially in a > federated system is a non-trivial task.
the way that this sort of thing seems to work best in IMAP (for example) is to use an immutable message and store separate mutable flags per mailbox per message - robert
