PavanKumar Chamarthi wrote in post #1087845:
please help me in this... I am unable to install pg gem file
[root@vdimc04 ~]# gem install pg -v '0.12.0' /usr/local/lib/ruby/1.9.1/yaml.rb:56:in `<top (required)>': It seems your ruby installation is missing psych (for YAML output). To eliminate this warning, please install libyaml and reinstall your ruby. Fetching: rake-compiler-0.8.1.gem (100%) Fetching: pg-0.12.0.gem (100%) Building native extensions. This could take a while... ERROR: Error installing pg: ERROR: Failed to build gem native extension.
/usr/local/bin/ruby extconf.rb checking for pg_config... no No pg_config... trying anyway. If building fails, please try again with --with-pg-config=/path/to/pg_config
checking for libpq-fe.h... no Can't find the 'libpq-fe.h header *** extconf.rb failed ***
It is in your own interest to provide more detail respecting your installation when reporting a problem and asking for help. For example, are you running CentOS-6 or 5? What point release? Are you using the stock PostgreSQl install, have you installed a different version from another respoitory, or have you built PostgreSQl yourself? In any case what version of Postgres?
Providing that you are running CentOS-6.x; and assuming that you are evidently not using the Postgres provided with that distribution; and guessing that you are likely using the pgdg-91-centos.repo; and also guessing that you are using either rvm or rbenv then you likely need to do something akin to the following
yum install postgresql91-devel libyaml gem install pg --with-pg-config=/usr/pgsql-9.1/bin/pg_config
HTH
