How to merge data from mysql schemas that have diverged?
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I have two servers that share an original ancestor codebase, but which have changed during the past couple of months in terms of database schema (I'm using mysql). I'm about to use the second one as my new production server, but I have to update the data (there are new users, there's new data related to those users, etc.). I want the data in the server that's now live, but has the old schema to have the authority, yet I want the schema in the new one to be the final one. So it's kind of a weird merge: I want data from the old server to be imported into a new server with a (not _vastly_) different schema.

I was thinking of simply making a dump of the server with the most up-to-date data, but then loading it wouldn't work since the schema has changed quite a bit.

I was also thinking on dumping the schema of the new server, applying it to a copy of the old one, _then_ dumping the data from the latter and loading it into the new one, but I'm not sure how to go about doing that and if it's the safest option.

I develop on mac OS X and both of my servers are debian.