Is it possible to remove some old revisions in order to compact database? I don't mean to revert anything or remove sth from the middle. I would like to just delete from database everything older than specified date. Is it possible?
"Deleting old revisions" is not possible.
If you want to compact storage, I can think of 2 options.
Run bzr reconcile. The main function of this command is to fix inconsistencies detected by bzr check, but as its help says, it may do some additional optimizations too:
At the same time it is run it may recompress data resulting in a potential saving in disk space or performance gain.
You may want to take a backup of the repo before you do this!
Replace your repository and branches with a clean new replica. You can create replicas of a Bazaar branch using the bzr branch or bzr push commands with a target location outside of your current shared repository (if you are using one), and the new replica branches will be automatically optimized and compact.
Example: replicate the standalone branch /srv/mybranch into /newsrv/mybranch:
bzr branch /srv/mybranch /newsrv/mybranch
Example: replicate the shared repository /srv/repo into /newsrv/newrepo:
bzr init-repo /newsrv/newrepo --no-trees
cd /srv/repo
bzr branches -R | while read branch; do bzr push -d "$branch" /newsrv/newrepo/"$branch" --create; done