I want to upgrade so that I can offer visual editor.

CentOS 6.6, 64 bit, postgresql database, php 5.3.3

I followed the instructions and using a browser:

* go to wiki//mw-config/index.php, language is OK so I click CONTINUE

* next page I am prompted for the upgrade key that I copy/paste, CONTINUE

* Environmental checks. Other than a warning about 'older version of the ICU project's library' all is OK, CONTINUE

* Database settings, enter username/password, CONTINUE

* Name page. I enter wiki name & admin details, select 'Im bored', CONTINUE

* Install page, CONTINUE

* I get database error: Error: 42P07 ERROR: relation "mwuser" already exists It appears to be trying to do a fresh install rather than an upgrade. But it asked for the upgrade key earlier ?

As root at the command line I run & get: # php maintenance/update.php MediaWiki 1.24.0 Updater

DB connection error: No database connection

What am I doing that is wrong ?