- Go here: http://www.oracle.com/technetwork/topics/intel-macsoft-096467.html
- Download the 64bit versions of instantclient-sqlplus, instantclient-sdk, instantclient-basic - the 32bit versions do not work with OSX 10.9
- Create directories at /opt/oracle
- Unzip instantclient-basic first, move to /opt/oracle (should add a folder - something like /opt/oracle/instantclient_11_2/)
- Unzip instantclient-sdk and move its contents to /opt/oracle/instantclient_11_2/
- Unzip instantclient-sqlplus and move its contents /opt/oracle/instantclient_11_2/
- Open Terminal (if you haven't already) and type...
- DYLD_LIBRARY_PATH=/opt/oracle/instantclient_11_2 export DYLD_LIBRARY_PATH
- ORACLE_HOME=/opt/oracle/instantclient_11_2 export ORACLE_HOME
- cd /opt/oracle/instantclient_11_2
- ln -s libclntsh.dylib.11.1 libclntsh.dylib (creates a symbolic link)
- env
- verify that DYLD_LIBRARY_PATH=/opt/oracle/instantclient_11_2 (be sure there's no trailing / after instantclient_11_2)
- verify ORACLE_HOME=/opt/oracle/instantclient_11_2
- gem install ruby-oci8
This guide is copied from this answer on Stack Overflow.