Warning
This version drops support for the database format that was introduced in version 0.9.0. Compact your older databases (that have not been compacted for a long time) before upgrading, or they will become inaccessible.
Warning
Version 1.2.1 contains important security fixes. Previous 1.2.x releases are not recommended for regular usage.
The interface to the _users and _replicator databases have been changed so that non-administrator users can see less information:
The new optional (but enabled by default) compression of disk files requires an upgrade of the on-disk format (5 -> 6) which occurs on creation for new databases and views, and on compaction for existing files. This format is not supported in previous releases, so rollback would require replication to the previous CouchDB release or restoring from backup.
Compression can be disabled by setting compression = none in your local.ini [couchdb] section, but the on-disk format will still be upgraded.