# Postgres-pr interface not found **URL:** \ **Category:** Rails\ **Created:** [April 18, 2007, 11:17pm UTC](https://www.ruby-forum.com/t/postgres-pr-interface-not-found/92387 "2007-04-18T23:17:16Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![blakeage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/b38774/32.png) [@blakeage](https://www.ruby-forum.com/u/blakeage)\ **Post date:** [April 18, 2007, 11:17pm UTC](https://www.ruby-forum.com/t/postgres-pr-interface-not-found/92387/1 "2007-04-18T23:17:16Z")
I’ve installed the postgres-pr gem, and it is found using gem list v0.4.0. In my active record source, inside the postgresql\_adapter.rb file, I’ve changed line 7 from: require\_library\_or\_gem ‘postgres’ unless self.class.const\_defined?(:PGconn) to: require\_library\_or\_gem ‘postgres-pr’ unless self.class.const\_defined?(:PGconn) …to try and force it to use the postgres-pr interface, but I get the following error when loading a page: no such file to load – postgres-pr Why can’t it find that gem? OSX 10.4.X - app server Winblows XP - db server ---
**Author:** ![blakeage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/b38774/32.png) [@blakeage](https://www.ruby-forum.com/u/blakeage)\ **Post date:** [April 18, 2007, 11:33pm UTC](https://www.ruby-forum.com/t/postgres-pr-interface-not-found/92387/2 "2007-04-18T23:33:08Z")
> Why can’t it find that gem? > I seem to have gotten around it by putting the full path to the gem, and > dropping the “-pr” from the gem (since there is no postgres-pr.rb file, > but there is a postgres.rb file in the postgres-pr folder). New code is: require\_library\_or\_gem ‘/usr/local/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres’ unless self.class.const\_defined?(:PGconn) Interesting that it can’t find a gem based on the name that lists when you execute “gem list”. But it’s more likely indicative of my noob understanding of the require\_library\_or\_gem function.