bashrc is the best place to add aliases and Bash related functions. The Bash shell looks for the . bashrc file in the home directory and executes it in the current shell using source.

Certain Linux machines won’t have ORACLE profile set globally for all users, So if you need to invoke oracle command line commands like tnsping from command line without navigating to ORACLE installation directory then you have to do the following.

Instructions

• Go to your home directory and update “.bashrc_profile” to add the following 

  # oracle profile
  if [ -f $HOME/.oracle ] ; then
     . $HOME/.oracle
  fi
  

• Go to your home directory and add a new file “.oracle” with below contents, The ORACLE_HOME will change based on your oracle installation directory and oracle version

  # oracle home path  
  export ORACLE_HOME=/opt/oracle/client/product/12.1.0/64bit_client  
  export TNS_ADMIN=$ORACLE_HOME/network/admin  
  export PATH=$ORACLE_HOME/bin:$ORACLE_HOME/OPatch:$PATH
  CLASSPATH=.:$ORACLE_HOME/jdbc/lib/classes12.zip:$ORACLE_HOME/jdbc/lib/nls_charset12.zip  
  export CLASSPATH  
  LD_LIBRARY_PATH=$ORACLE_HOME/lib  
  export LD_LIBRARY_PATH  
  export PATH=$ORACLE_HOME/bin:$PATH