def default_fields_for(value, operator = nil)

      column_types  = [:virtual]
      column_types += [:string, :text]                if [nil, :like, :unlike, :ne, :eq].include?(operator)
      column_types += [:double, :float, :decimal]     if value =~ NUMERICAL_REGXP
      column_types += [:integer]                      if value =~ INTEGER_REGXP
      column_types += [:uuid]                         if value =~ UUID_REGXP
      column_types += [:datetime, :date, :timestamp]  if (parse_temporal(value))

      default_fields.select { |field| !field.set? && column_types.include?(field.type) }
    end
def default_fields_for(value, operator = nil)

      column_types  = [:virtual]
      column_types += [:string, :text]                if [nil, :like, :unlike, :ne, :eq].include?(operator)
      column_types += [:double, :float, :decimal]     if value =~ NUMERICAL_REGXP
      column_types += [:integer]                      if value =~ INTEGER_REGXP
      column_types += [:uuid]                         if value =~ UUID_REGXP
      column_types += [:datetime, :date, :timestamp]  if (parse_temporal(value))

      default_fields.select { |field| !field.set? && column_types.include?(field.type) }
    end
Returns a list of appropriate fields to search in given a search keyword and operator.