quote

# File activerecord/lib/active_record/connection_adapters/abstract/quoting.rb, line 8
      def quote(value, column = nil)
        # records are quoted as their primary key
        return value.quoted_id if value.respond_to?(:quoted_id)

        case value
        when String, ActiveSupport::Multibyte::Chars
          value = value.to_s
          return "'#{quote_string(value)}'" unless column

          case column.type
          when :integer then value.to_i.to_s
          when :float then value.to_f.to_s
          else
            "'#{quote_string(value)}'"
          end

        when true, false
          if column && column.type == :integer
            value ? '1' : '0'
          else
            value ? quoted_true : quoted_false
          end
          # BigDecimals need to be put in a non-normalized form and quoted.
        when nil        then "NULL"
        when BigDecimal then value.to_s('F')
        when Numeric, ActiveSupport::Duration
          if column.try(:type) == :string
            quote(value.to_s, column)
          else
            value.to_s
          end
        when Date, Time then "'#{quoted_date(value)}'"
        when Symbol     then "'#{quote_string(value.to_s)}'"
        when Class      then "'#{value.to_s}'"
        else
          "'#{quote_string(YAML.dump(value))}'"
        end
      end