Rails Seralized My Object One Way & Refuses to Change

I have a rails class that serializes one attribute.

    class Statistic < ActiveRecord::Base       serialize :userlist     end

When a statistic object is loaded and it's userlist changed from a String to an Array userlist always gets serialized back into a String. Objects that are properly deserialized into Arrays stay that way. The framework seems to remember and deserialize :userlist into a String even if it went in as an Array.

  >> s = Statistic.find 238   => #<Statistic id: 238, userlist: "--- \n- 2222437\n- \"99779\"\n- \"120429\"\n- \"210503\"\n- 32...">   # Note here: :userlist is an Array in YAML. Why doesn't it get correctly deserialized?

  >> s.userlist.class   => String   >> s.userlist = s.userlist.split(/\s+/)

  >> s.userlist.class   => Array

  >> s.save   => true

  >> s.reload   => #<Statistic id: 238,userlist: "--- \n- 2222437\n- \"99779\"\n- \"120429\"\n- \"210503\"\n- 32...">

  >> s.userlist.class   => String

The goal of this exercise is to convert all String userlists to Array. If I change the class (serialize :userlist, Array) before converting I get TypeMismatch exceptions.

    ActiveRecord::SerializationTypeMismatch: userlist was supposed to be a Array, but was a String

Is there a way to force AR to interpret userlist as an Array?

% rails --version Rails 2.3.4

Related, but doesn't solve the problem: http://groups.google.com/group/rubyonrails-talk/browse_thread/thread/e548784faa7f9cef/c24380c98c64cbc3

Found the problem. The String is not correct YAML:

YAML::load(s.userlist)

ArgumentError: syntax error:ScannerException while scanning a quoted scalar we had this found unexpected end of stream from (irb):8

The code from AR::B is

      def object_from_yaml(string)         return string unless string.is_a?(String) && string =~ /^---/         YAML::load(string) rescue string       end

--Dean

This doesn't explain why the userlist isn't correctly serialized & deserialized when reloaded.... --Dean

This doesn't explain why the userlist isn't correctly serialized & deserialized when reloaded....

What's the column type & how long is the data ? Is it getting truncated because of the size of the column ?

Fred

This occurred to me too. The column type is text. I don't recall the length, but it was between 50,000 & 100,000 characters. I'll check the max_allowed_packet setting when I get back to work.

http://dev.mysql.com/doc/refman/5.0/en/blob.html

--Dean

This occurred to me too. The column type is text. I don't recall the length, but it was between 50,000 & 100,000 characters. I'll check the max_allowed_packet setting when I get back to work.

Text columns have a 65535 limit (mediumtext and longtext columns can take much more)

Fred

> This occurred to me too. The column type is text. I don't recall the > length, but it was between 50,000 & 100,000 characters. I'll check > the max_allowed_packet setting when I get back to work.

Text columns have a 65535 limit (mediumtext and longtext columns can take much more)

Fred

Thanks. That is the problem. 65535 characters on the nose.

--Dean