Ray Saintonge wrote:
Of course we've had unplanned downtime that has lasted for more than an hour. Then too en:wikipedia has so far resisted converting to Unicode. :-)
All I'm saying is that time is an important parameter, and that you can calculate how much time will be needed, and set a limit to what is acceptable (if it means downtime).
If you have lots of data (e.g. the English "old" table), it is often an advantage if you can convert one piece at a time. I guess this could be done for converting the old table to Unicode. You could add column (or a separate table) that indicates if entry X of the old table is in Unicode, alter the software to look in this column, then start the conversion one article at a time as a low priority background process. After the conversion is completed, the software can be altered back again.
That strategy would be the total opposite of defining a unified export dump format and stop everything for a week to do a dump, convert, and import. Just like a pipeline and a tanker ship are two different ways to transport oil.