On Wed, Mar 25, 2009 at 6:02 PM, Thomas Dalton <thomas.dalton(a)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.