  def self.count_ack_users(item_id)
    SqlHelper.validate_token([item_id])
    return Comment.where("(item_id=#{item_id.to_i}) and (xtype='#{Comment::XTYPE_DIST_ACK}')").count
  end
The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.