ok I confess I did not take that backup warning seriously. I had yesterday's automatic backup, thank god.
But a warning that the upgrade ROUTINELY crashes the database, if the database is big, would have alerted me and convinced to backup. Still, it took me 5 hours of work to find out the database crashed, 4 hours of work to find the fix, another 5 hours of work to redo the database upgrade. Then more hours of work to look for the fix on the lost PM. That could be easier!!!
Also, as it is completely impossible to do an online altertable that takes 90 minutes to complete, they should offer another option, a command line php routine, and a command line mysql command list. I had to build my command line php files myself (after all it is 9 steps), and only after I already crashed the database.
Or find out how to split the stuff up in pieces of 10 000 posts at a time, or whatever. Like change 10 000 posts, output a message (to keep the connection alive), then do the next 10 000, output a message, etc.
