I tried in maintenance mode (on) with the --no interaction option and got the same result…
(Full command: php occ db:convert-type --all-apps --clear-schema --no-interaction --password="..." mysql nextcloudDBUser 127.0.0.1:3306 nextcloudDB)
Should I clear the database before trying to convert again the sqlite database? I was concern about not messing up any internal database migration progress/state.
I wonder: would it be possible that the occ command (or some internal state in wordpress, stored in files) is corrupted, preventing a normal database conversion? I keep having this PHP Memory Limit warning but according my phpinfo(), it is as configured at 1024MB…
I had a look at the conf/config.php file and noticed that sqlite3 is still the used database, as expected since the conversion is incomplete.