ActiveRecord: Can't store a class derived from AR::Base

rubyonrails-talk
1

Hi,

try to use ActiveRecord for my little standalone application, without the rails environment. Here is my first try

8<--------------------------------------------------

# Main if __FILE__ == $0 then

   ActiveRecord::Base.establish_connection(      :adapter => 'mysql',      :host => @config[:sql][:hostname],      :database => @config[:sql][:database],      :username => @config[:sql][:username],      :password => @config[:sql][:password]    )

   puts 'Erzeuge ein paar Knoten und speicher diese in der DB: '

   80.times do |i|      aNode = Node.new("node_#{i}",1)      print '.'      aNode.save!    end

end

8<--------------------------------------------------

@config is well initialized, the ActiveRecord connects to my DB as you'll expected. But the call aNode.save! fails with this error:

Erzeuge ein paar Knoten und speicher diese in der DB: .c:/ruby/lib/ruby/gems/1.8/gems/activerecord-2.2.2/lib/active_record/transactions.rb:164:in `rollback_active_record_state!': undefined method `delete' for nil:NilClass (NoMethodError)          from c:/ruby/lib/ruby/gems/1.8/gems/activerecord-2.2.2/lib/active_record/transactions.rb:150:in `save!'          from main.rb:35          from main.rb:32:in `times'          from main.rb:32

Mmm, but I have looked in transactions.rb at line 150 and 164, looks fine for me. My AR gems are

D:\ramantics>gem list --local

*** LOCAL GEMS ***

actionmailer (2.2.2) actionpack (2.2.2) activerecord (2.2.2) activeresource (2.2.2) activesupport (2.2.2) fxri (0.3.7, 0.3.6) fxruby (1.6.17, 1.6.6) hpricot (0.6.164, 0.4) log4r (1.0.5) mysql (2.7.3) ptools (1.1.6) rails (2.2.2) rake (0.8.3, 0.7.2) rubygems-update (1.3.1) sources (0.0.1) test-unit (2.0.2) win32-api (1.2.2) win32-clipboard (0.4.4, 0.4.1) win32-dir (0.3.2, 0.3.1) win32-eventlog (0.5.0, 0.4.3) win32-file (0.6.0, 0.5.3) win32-file-stat (1.3.2, 1.2.3) win32-process (0.6.0, 0.5.1) win32-sapi (0.1.4, 0.1.3) win32-sound (0.4.1, 0.4.0) windows-api (0.2.4) windows-pr (0.9.8, 0.6.2)

Has anyone an idea where I made the mistake? Thanks a lot.

g,

Daniel

2

Has anyone an idea where I made the mistake? Thanks a lot.

Have you override initialize in you Node class ?

Fred

3

Frederick Cheung schrieb:

Have you override initialize in you Node class ?

Hi Fred,

aaah yes. I already found the problem. As you mentioned, I overwrote initialize in my Node class which inherits AR::Base.

Damn I didn't know that this isn't allowed :frowning: Fixed failures lead to better code *g*

Thanks for your response.

Daniel

4

Frederick Cheung schrieb:

Have you override initialize in you Node class ?

Hi Fred,

aaah yes. I already found the problem. As you mentioned, I overwrote initialize in my Node class which inherits AR::Base.

Damn I didn't know that this isn't allowed :frowning: Fixed failures lead to better code *g*

You can override initialize, but you just need to ensure you call the
superclass implementation properly.

Fred

5

Frederick Cheung schrieb:

You can override initialize, but you just need to ensure you call the superclass implementation properly.

Oh, thanks for this additional information, I see I've to read the docs ,)

g,

Daniel