You have to follow this instruction:
NOTE: If you are upgrading to Moodle 2.3, make sure you have upgraded the questionnaire module to the latest version of Moodle 2.2, in your Moodle 2.2 codebase before upgrading to Moodle 2.3.
Moodle dropped/changed many of the DML API functions after 2.2, so the upgrade steps from anything earlier than 2.2 will not work after 2.2.