Ruby on Rails Oracle DB connection - ruby-on-rails

Question

My main database is a local mysql database, however I would like to occasionally connect to an Oracle database directly in my applications code.
The oracle database is hosted on another RHEL server.
I was unsuccessfull tried to install the ruby-OCI8 gem (ERROR: Failed to build gem native extension.)
I am wondering whether the oracle database has to be local in order to use this gem, or if there are any better ways of achieving this.
gem install ruby-oci8
Building native extensions. This could take a while...
ERROR: Error installing ruby-oci8:
ERROR: Failed to build gem native extension.
/usr/bin/ruby extconf.rb
checking for load library path...
LD_LIBRARY_PATH...
checking /opt/instantclient... yes
/opt/instantclient/libclntsh.so.11.1 looks like an instant client.
checking for cc... *** 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=/usr/bin/ruby
--with-instant-client
--without-instant-client
./oraconf.rb:562:in `check_cc': RuntimeError (RuntimeError)
from ./oraconf.rb:549:in `init'
from ./oraconf.rb:1001:in `initialize'
from ./oraconf.rb:343:in `new'
from ./oraconf.rb:343:in `get'
from extconf.rb:18
ng
---------------------------------------------------
Error Message:
C compiler doesn't work correctly.
Backtrace:
./oraconf.rb:562:in `check_cc'
./oraconf.rb:549:in `init'
./oraconf.rb:1001:in `initialize'
./oraconf.rb:343:in `new'
./oraconf.rb:343:in `get'
extconf.rb:18
---------------------------------------------------
See:
* http://ruby-oci8.rubyforge.org/en/HowToInstall.html
* http://ruby-oci8.rubyforge.org/en/ReportInstallProblem.html
I checked the mkmf.log file:
"gcc -o conftest -I. -I/usr/lib64/ruby/1.8/x86_64-linux -I. -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fs tack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fno-strict-aliasing -fPIC conftest.c -L. -L/usr/lib64 -L. -rdynamic -Wl,-export-dynamic -lruby-static -lpthread -lrt -ldl -lcrypt -lm -lc"
/usr/bin/ld: skipping incompatible /usr/lib/libruby-static.a when searching for -lruby-static
/usr/bin/ld: cannot find -lruby-static
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: int main() { return 0; }
8 /* end */

Answer 1

At first you need to install Oracle Instant Client - choose corresponding Linux 32-bit or 64-bit binaries. To be safe use older version 10.2.0.4 which I use in all my Ruby and Oracle projects. Install Basic, SDK and SQL*Plus packages.
Then include Oracle Instant Client installation directory in LD_LIBRARY_PATH environment variable so that Oracle Instant Client dynamic libraries would be in load path.
Then try to install ruby-oci8 gem.
Afterwards install activerecord-oracle_enhanced-adapter gem to be able to access Oracle database from ActiveRecord.
I have posted instructions how to install ruby-oci8 on Mac OS X - majority of this applies to Linux as well (DYLD_LIBRARY_PATH on Mac corresponds to LD_LIBRARY_PATH on Linux).
In addition I have created Sprinkle recipe for automated Oracle client installation on Linux - probably it is not the best way to start with this but in case you want to build automated server installation scripts then you can take a look on it.

Answer 2

See if this blog post helps you in getting through the OCI gem install http://jessehu.wordpress.com/2008/07/03/ruby-oci8-gem-available-2/

Answer 3

You can install the ruby-oci8 gem like below,
LD_LIBRARY_PATH=/local/home/soundar/instantclient_11_2 gem install ruby-oci8
Note: LD_LIBRARY_PATH is a enviroment variable set by oracle instant client directory path