[Pkg-erlang-devel] Bug#578868: Bug#578868: couchdb: database migration should be automatic

[Sam Bisbee]

On Fri, Apr 23, 2010 at 11:15:10AM +0200, Stefan Praszalowicz wrote:
> Package: couchdb
> Version: 0.11.0-1
> Severity: normal
> Tags: squeeze
> 
> README.Debian says "the database directory is partitioned by the CouchDB
> release number of the database format in use" and "Before you upgrade to a
> new
> version [...]  you should export [...]  and import the data into the new
> database after the upgrade".
> 
> This is quite awkward: no prior warning when upgrading, and the old binaries
> aren't
> here anymore after the upgrade is done.
> 
> A quick, short-term minimal fix would be warning the user about the need for
> data migration, offering to abort the upgrade, and pointing to the dump/load
> procedure or tools.  In the long run, the dump/load operations should
> probably
> be automated by the package.

Thanks for reporting Stefan - input is always appreciated.

I've marked the ticket as "wishlist" because this is more of an experience
issue than an actual bug. The data from previous versions is not lost due to
the version number partitioning of directories.

However, I agree that this is not a nice experience when upgrading. I will most
likely use a notice as you suggest until I have time to more fully vet
automated options: there could be issues when upgrading between versions that
store databases differently, if the database is particularly large (might not
have been compacted recently or could have a lot of documents), scarce system
resources, etc.

If an automated process is exposed during upgrade, it will be optional and
include a note that one can use replication or dump/load after the upgrade.

Cheers,

--
Sam Bisbee