Ruby on Rails

On Thursday, September 26, 2019 at 4:32:10 PM UTC-4, Ariel Juodziukynas wrote:

The easiest but too big is a text columns so you can use activerecord' serialization of attributes to save anything you want on a text field and activerecord will handle casting.

You could use a string column if you know your values won't be too big (VARCHAR(255)) and you know what types you want to accept and handle serialization yourself like:

    def value=(something)
      val = if value.is_a?(Integer)

              "integer:#{something}"

            elsif value.is_a?(String)

              "string:#{something}"

            elsif value.is_a?(Date)

              "date:#{something}

            # etc...

      write_attribute(:value, val)

    end

    def value

      type, val = read_attribute(:value).split(':')

      case type

      when "integer" then val.to_i

      when "string" then val

      when "date" then Date.parse(val)

      etc...

    end

           

El jue., 26 sept. 2019 a las 17:17, fugee ohu (<fuge...@gmail.com>) escribió:

On Monday, September 16, 2019 at 4:31:29 PM UTC-4, Ariel Juodziukynas wrote:

Personally, I would do this:

auctions table

(with the basic shared information of all auctions and an "auction type"))

properties table

property_name (like network, carrier, publisher, etc)

auction_type (like cellphone, book, etc)

auctions_properties

auction_id

property_id

value

That way you can have any number of auction types with any number of specific properties with just 3 tables.

Note that the "value" column would be some string variation (VARCHAR, CHAR, TEXT, etc) depending on your needs, maybe you want to redesign it a little if you want to store different types. Like if you want to store an integer (and retrieve an integer) you'll have to save the original type and reparse it (you could use serialization but that requires a TEXT column and maybe you can't use that many space)

El lun., 16 sept. 2019 a las 17:19, fugee ohu (<fuge...@gmail.com>) escribió:

I was looking at some auction projects that use a single listings table for all auctions but I know on auction sites the form will be different for different types of items like if you're selling a cell phone there'll be a form field for network, carrier, whatever and if you're selling a book there'll be form fields for publisher, year of publication,  so they would have separate tables I assume for books, cell phones, etc? Then how would they treat them all as one?

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What data type do you suggest for value column

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 If I'm using a string column then whatever value is put in it is a string, so I don't understand all these "'if value.is_a?" conditions

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