I just upgraded to piwik 1.20 and crashed my database.
I thought the best way would be to install piwik completely new and then import the archive tables (piwik_archive_numeric_2010_01 … and piwik_archive_blob_2010_01 …).
It seems this was wrong. Piwik does not show me any old visits.
Is there a way to access to old archive files? What additional tables or cells do I have to copy?