Postgres: Install of an additional language fails

I installed the current staging branch using postgresql successfully. Afterwards I tried to install an additional language in the backend but it failed with the following message:

0 Database query failed (error # %s): %s SQL=SELECT "update_id" FROM "aehqu_updates" WHERE element = 'de-DE' AND type = 'language' AND client_id = '' AND folder = '' 

After applying this patch the installation went fine. I borrowed the idea from #1695.
Merge pull request #4923 from waader/patch-3

Postgres: Install of an additional language fails