On Wed, Mar 25, 2009 at 6:02 PM, Thomas Dalton thomas.dalton@gmail.com wrote:
An extra column in any table with a "user id" column for "original user id" (which would be identical to user id for the vast majority of rows) would be sufficient for most unmerges. There would still be a problem if an account was involved in more than one merge, though.
That's a *lot* of extra columns for such a marginal feature. More likely we'd do something like log a blob that has a serialized list of everything changed. (This would require actually figuring out everything that was changed, of course, which already complicates things and probably slows them down.) If we want to revert, we'd load up the blob and build the queries from it.