def version
      SelectVersionsQuery.new.fetch_first || Version.new('0')
    rescue Cassandra::Errors::InvalidError
      raise uninitialized_error
    end
def version
      SelectVersionsQuery.new.fetch_first || Version.new('0')
    rescue Cassandra::Errors::InvalidError
      raise uninitialized_error
    end
The current schema version
 @return [Version]