[PATCH v2 05/14] lib: Database version 3: Introduce fine-grained "features"

2014-07-29 Thread Austin Clements
Previously, our database schema was versioned by a single number. Each database schema change had to occur "atomically" in Notmuch's development history: before some commit, Notmuch used version N, after that commit, it used version N+1. Hence, each new schema version could introduce only one chan

[PATCH v2 05/14] lib: Database version 3: Introduce fine-grained "features"

2014-07-29 Thread Austin Clements
Previously, our database schema was versioned by a single number. Each database schema change had to occur "atomically" in Notmuch's development history: before some commit, Notmuch used version N, after that commit, it used version N+1. Hence, each new schema version could introduce only one chan