# File lib/grit/git-ruby/commit_db.rb, line 12
      def initialize(git_obj, index_location = nil)
        @git = git_obj
        db_file = File.join(index_location || @git.git_dir, 'commit_db')
        if !File.exists?(db_file)
          @db = Sequel.open "sqlite:///#{db_file}"
          setup_tables
        else
          @db = Sequel.open "sqlite:///#{db_file}"
        end
      end