def print_operations
      ops = @operations.reverse.map do |op|
        attr_s = " #{op.attribute}" if op.attribute
        "#{op.type.to_s.capitalize_first} #{op.subject.qp}#{attr_s}"
      end
      ops.qp
    end
def print_operations
      ops = @operations.reverse.map do |op|
        attr_s = " #{op.attribute}" if op.attribute
        "#{op.type.to_s.capitalize_first} #{op.subject.qp}#{attr_s}"
      end
      ops.qp
    end
Returns the current database operation stack as a String.