Comment 2 for bug 1517658

To test:

0. Have a Postgres version prior to 9.1 installed.
1. Install a Mahara version prior to 1.10
2. Upgrade Mahara to 1.10 or later.

Expected result: Clean upgrade
Actual result: Error stack seen in the bug description above.

The artefact upgrade code will get exercised even when upgrading a clean Mahara install, because there are a few artefacts created by the system (like the admin user's firstname and lastname).

Cheers,
Aaron