Sites using 1.9.x, but originally installed with < 1.7, fail upgrading to 2.0 due to null fields in mdl_user table

1. Install Moodle 1.6 using Postgres. I had some issues here with getting Moodle's installer to generate the config.php as it could not connect to the database. I ended up having to create the file myself and specify the port. Eg. $CFG->dbtype = 'postgres7'; // mysql or postgres7 (for now) $CFG->dbhost = 'localhost'; // eg localhost or db.isp.com $CFG->dbname = 'name'; // database name, eg moodle $CFG->dbuser = 'user'; // your database username $CFG->dbpass = 'pass'; // your database password $CFG->dbport = '5432'; $CFG->prefix = 'mdl_'; // Prefix to use for all table names $CFG->dbpersist = false; // Should database connections be reused? Remove all references of insertion to logs (eg. INSERT INTO prefix_log_display (module, action, mtable, field) VALUES ('forum', 'add', 'forum', 'name')) from lib/db/postgres7.sql and mod/forum/db/postgres7.sql before the upgrade as they will cause database errors. This is an issue in 1.6/1.7 so not reporting. 2. Upgrade to 1.9, then to 2.1 3. Ensure there are no null column errors. eg. Debug info: ERROR: column "lastip" contains null values. 4. Compare the upgraded user table field attributes (default values, length etc) to those of a fresh install to ensure they are the same (note, they will be in the wrong order as the upgrade to 1.9 changes this (another issue?)) 5. Repeat, except for step 2 upgrade to 2.2