我使用的是Ruby on Rails 3.1预版本。我喜欢使用PostgreSQL,但问题是安装pg gem。它给了我以下错误:

$ gem install pg
Building native extensions.  This could take a while...
ERROR:  Error installing pg:
    ERROR: Failed to build gem native extension.

        /home/u/.rvm/rubies/ruby-1.9.2-p0/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 ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
    --with-opt-dir
    --without-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/home/u/.rvm/rubies/ruby-1.9.2-p0/bin/ruby
    --with-pg
    --without-pg
    --with-pg-dir
    --without-pg-dir
    --with-pg-include
    --without-pg-include=${pg-dir}/include
    --with-pg-lib
    --without-pg-lib=${pg-dir}/lib
    --with-pg-config
    --without-pg-config
    --with-pg_config
    --without-pg_config
    Gem files will remain installed in /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0 for inspection.
    Results logged to /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0/ext/gem_make.out

我怎么解决这个问题?


当前回答

在OS X 10.9 (Mavericks)上,我自定义安装了postgresql,然后我必须rvm重新安装Ruby。我现在很开心:)

其他回答

在Arch Linux上,你需要安装postgresql-libs:

sudo pacman -Syu postgresql-libs

郑重声明:

Ruby on Rails 4应用程序在OS X与PostgresApp(在这种情况下需要0.17.1版本-有点老项目):

gem install pg -v '0.17.1' -- --with-pg-config=/Applications/Postgres.app/Contents/Versions/9.3/bin/pg_config

在OS X和MacPorts上,PostgreSQL不再需要-devel包。安装pg gem的步骤如下:

~ > sudo port install postgresql-devel
...
Error: postgresql-devel has been replaced by postgresql91; please install that port instead
~ > gem install pg -v '0.17.1' -- --with-pg-config=/opt/local/lib/postgresql95/bin/pg_config

参见这篇文章。

我在通过asdf安装postgres时遇到了同样的错误。pg-config解决方案对我不起作用。相反,我必须找到包含该文件的postgres include文件夹,并运行带有——with-pg-include标志的命令

gem install pg -- --with-pg-include=/<path>/.asdf/installs/postgres/<version>/include

我在Mac OS上也有同样的问题,但我在终端上使用以下方法轻松安装了PostgreSQL gem:

ARCHFLAGS="-arch x86_64" gem install pg

(我先用brew install PostgreSQL安装PostgreSQL。)