Getting unexpected string value for NULL values

rubyonrails-talk
1

Upgrading a legacy app from 1.x to 2.1....

The app has a Product model, and the Products migration contains:

      t.column :serial_no, :string, :default => :null

But if I create new, empty Product object like this in script/console:

p = Product.new

The serial_no field is a string with this value:

p.serial_no

=> "--- :null\n"

I would have expected nil instead of a string representation of null. This is causing a slew of tests to break.

Why is this happening in 2.1?

The app uses Postgresql 8.3, if that matters.

Thanks, Jeff

2

Upgrading a legacy app from 1.x to 2.1....

The app has a Product model, and the Products migration contains:

     t.column :serial_no, :string, :default => :null

You probably mean to have:

  :default => nil

which is the same as not specifying a result.

But if I create new, empty Product object like this in script/console:

p = Product.new

The serial_no field is a string with this value:

p.serial_no

=> "--- :null\n"

I would have expected nil instead of a string representation of null. This is causing a slew of tests to break.

You have a symbol :null rather than nil or "null". The YAML serialization you see is a reasonable way to store a Ruby symbol in a database.

Why is this happening in 2.1?

The app uses Postgresql 8.3, if that matters.

Thanks, Jeff

You're welcome, -Rob

Rob Biedenharn http://agileconsultingllc.com Rob@AgileConsultingLLC.com

3

Ugh... yes, thanks for spotting that. This is a legacy app that I didn't write, but I guess I can simply write a new migration to change the column default.

Thanks! Jeff

REST with Rails Saturday, Oct 4, 2008 Austin, TX http://www.purpleworkshops.com/workshops/rest-and-web-services