From PostgreSQL wiki
Over the years, PostgreSQL and common software around it has accumulated its share of usability problems. While experienced users are used to these problems and often don't even notice that they are there, these issues frequently trip up newbies.
This article aims to collect various reviews and studies posted about PostgreSQL's usability, to make sure they don't simply get lost in mailing list archives.
- Usability write-up - looking at Pg, especially PgAdmin-III and Pg on Windows, from an inexperienced user PoV
- database schema quality survey & postgresql pitfalls
See also: Usability Challenges