def ft_del_all
      @model.all.each {|record| ft_del(record: record) }
      ft_optimize
    rescue Exception => e
      Rails.logger.error e if defined? Rails
      return e.message
    end
def ft_del_all
      @model.all.each {|record| ft_del(record: record) }
      ft_optimize
    rescue Exception => e
      Rails.logger.error e if defined? Rails
      return e.message
    end
delete all records in specific model

 @return [String]