GJ> Running update.php leaves everything as it was before, but a fresh
GJ> install produces the new table structure (with a blob for the URL).
GJ> Both seem to work, but I am concerned about how to move to the new
GJ> table structure (table interwiki).
So that makes at least the third version of what one's interwiki table
will look like, depending on what version one started using MediaWiki
(and updating dutifully since.)
https://bugzilla.wikimedia.org/show_bug.cgi?id=12200