I spent lots of time searching this. SVN Red book http://svnbook.red-bean.com/ do not explain it properly. So here i am trying to Explain it.
1. Make sure you have SVN_EDITOR veriable set.
2. Type following command on Terminal
svn propset svn:ignore “*” log/
this will ignore all the logs file from your rails folder structure. You have to delete all the logs file before running this command.
3. If you want specifically Ignore only one file from directory e.g i want to ignore schema.rb from db director into rails folder structure.
svn propset svn:ignore “schema.rb” db/
4. Commit and apply changes