On Sun, Nov 6, 2011 at 4:07 PM, Jani Nikula <jani@nikula.org> wrote:
> On Sun,  6 Nov 2011 12:17:36 -0500, Austin Clements <amdragon@MIT.EDU> wrote:
>> Taking full advantage of this requires a database rebuild, but it will
>> fall back to the old behavior for messages that do not have headers
>> stored in the database.
>
> ...what's the most convenient way of rebuilding the database while
> preserving my tags etc.? If this was merged, would an older version of
> notmuch choke on the rebuilt database with these headers? (To me it
> looks like it would be fine.)

The standard way to rebuild the database is to do a notmuch dump, move
.notmuch out of the way, notmuch new, then notmuch restore.  Some day
this process should be made automatic.

Old versions of notmuch will be blissfully unaware of the new headers
stored in the database.  They can even safely add messages to an
upgraded database without breaking new versions of notmuch.