Migrations

rubyonrails-talk
1

Hi there

I would like to get some advice on migrations. New on Rails, I do no exactly understand what is going on here.

I have created a table "tax" sucessfully using this code in a migration file:

class CreateTax < ActiveRecord::Migration   def self.up     create_table :tax do |t|       t.column(:rate, :integer, :default => 0)       # more     end   end

  def self.down     drop_table :tax   end end

Later, in a second step, I tried to populate this table with test data using this code:

class TestTax < ActiveRecord::Migration   def self.up     down

    tax = Tax.create(           :rate => 0,           :description => '(none}',           is_default => 0)     tax.save!     # more records...

  end

  def self.down       Tax.delete_all   end end

This leads to "uninitialized constant TestTax::Tax" printed by rake.

Originally, I tried to follow the standard Rail conventions about using plurals, but this did not work either. Only when I got an error message about "Taxis" (??) I thought, well, plurals seems to cause problems instead of being really helpfull, so I added:

Inflector.inflections do |inflect|     inflect.uncountable %w( tax ) end

to environment.rb

What do I miss here?

I have other problems with migrations which let me think that I do not really understand what is going on. For example, I have the impression that the name of a migration is in some respect taken into account. (I am not talking about the "xxx_" part of course).

I tried to find my way but only got the impression of inconsistency.

Is there a good source of information of how rails Rails is really managing Migrations, with all rules/assumptions?

Thanks for help in advance!

Kai