[TYPO3-dev] Weird Upgrade Problem 4.1.x -> 4.2.x

[Martin Kutschker]

Peter Russ schrieb:
> On a system a new customer asked us to upgrade we experience weird
> upgrade problems with Mysql:
> MySQL 5.0.51 running on utf-8

Did you use utf8 before the TYPO3 upgrade?

A BLOB has no charset, but a TEXT has. So if you convert the DB from
iso-8859-1 to utf8, the BLOB fields are not converted. If you change the
BLOBs later to TEXT fields they are broken as you have now iso-8859-1
data in utf8 fields.

So you must change the BLOBs to TEXT fields and *after* that convert the
DB to utf8.

Masi