Nil.each

[Gerhardk]

Hey

I am trying to migrate for n postgres database to mysql.
When I run rake db:dump everything works.
When I run rake db:load it gives me an nil.each error.
I know I have empty tables, can you advise what I need to do.

Thanks

[dimitarvp]

Dumped MySQL production DB without a problem

Tried importing it into development SQLite3 DB and I got this:

...
** Invoke db:data:load (first_time)
** Invoke environment
** Execute db:data:load
rake aborted!
You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.each
C:/code/testmysql/vendor/plugins/yaml_db/lib/serialization_helper.rb:85:in load_records' C:/code/testmysql/vendor/plugins/yaml_db/lib/serialization_helper.rb:74:inload_table'
C:/code/testmysql/vendor/plugins/yaml_db/lib/yaml_db.rb:63:in block (2 levels) in load_documents' C:/code/testmysql/vendor/plugins/yaml_db/lib/yaml_db.rb:61:ineach'
C:/code/testmysql/vendor/plugins/yaml_db/lib/yaml_db.rb:61:in block in load_documents' C:/Ruby192/lib/ruby/1.9.1/psych/deprecated.rb:30:ineach'
C:/Ruby192/lib/ruby/1.9.1/psych/deprecated.rb:30:in load_documents' C:/code/testmysql/vendor/plugins/yaml_db/lib/yaml_db.rb:60:inload_documents'
C:/code/testmysql/vendor/plugins/yaml_db/lib/serialization_helper.rb:57:in block in load' C:/Ruby192/lib/ruby/gems/1.9.1/gems/activerecord-3.0.9/lib/active_record/connection_adapters/abstract/database _statements.rb:139:intransaction'
C:/code/testmysql/vendor/plugins/yaml_db/lib/serialization_helper.rb:56:in load' C:/code/testmysql/vendor/plugins/yaml_db/lib/serialization_helper.rb:31:inload'
C:/code/testmysql/vendor/plugins/yaml_db/lib/tasks/yaml_db_tasks.rake:35:in block (3 levels) in <top (require d)>' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:205:incall'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:205:in block in execute' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:200:ineach'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:200:in execute' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:158:inblock in invoke_with_call_chain'
C:/Ruby192/lib/ruby/1.9.1/monitor.rb:201:in mon_synchronize' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:151:ininvoke_with_call_chain'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:176:in block in invoke_prerequisites' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:174:ineach'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:174:in invoke_prerequisites' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:157:inblock in invoke_with_call_chain'
C:/Ruby192/lib/ruby/1.9.1/monitor.rb:201:in mon_synchronize' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:151:ininvoke_with_call_chain'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/task.rb:144:in invoke' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:112:ininvoke_task'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:90:in block (2 levels) in top_level' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:90:ineach'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:90:in block in top_level' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:129:instandard_exception_handling'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:84:in top_level' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:62:inblock in run'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:129:in standard_exception_handling' C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/lib/rake/application.rb:59:inrun'
C:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.9.2/bin/rake:32:in <top (required)>' C:/Ruby192/bin/rake:19:inload'
C:/Ruby192/bin/rake:19:in `

'
Tasks: TOP => db:load => db:data:load

[janlelis]

might be this bug: #18 (use syck for dumping)

[wejrowski]

I'm on EngineYard and I'm trying to use the yaml_db gem to load data I had locally that I saved to db/data.yml with the gem. I'm running

rake db:data:load

And I'm getting this same exact error. I've tried forcing the YAML engine to syck and also tried psych on Engineyard but neither is working. I'm not sure how to load the yml file.

Any ideas?

[fivetwentysix]

Same here

[master][~/Sites/boss-mocha] bundle exec rake db:data:load --trace
*\* Invoke db:data:load (first_time)
*\* Invoke environment (first_time)
*\* Execute environment
*\* Execute db:data:load
rake aborted!
You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.each
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/serialization_helper.rb:85:in `load_records'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/serialization_helper.rb:74:in`load_table'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/yaml_db.rb:63:in `block (2 levels) in load_documents'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/yaml_db.rb:61:in`each'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/yaml_db.rb:61:in `block in load_documents'
/Users/pma/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/syck.rb:235:in`call'
/Users/pma/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/syck.rb:235:in `load_documents'
/Users/pma/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/syck.rb:235:in`load_documents'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/yaml_db.rb:60:in `load_documents'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/serialization_helper.rb:57:in`block in load'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.0.10/lib/active_record/connection_adapters/abstract/database_statements.rb:139:in `transaction'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/serialization_helper.rb:56:in`load'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/serialization_helper.rb:31:in `load'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/yaml_db-0.2.1/lib/tasks/yaml_db_tasks.rake:35:in`block (3 levels) in <top (required)>'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:205:in `call'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:205:in`block in execute'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:200:in `each'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:200:in`execute'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:158:in `block in invoke_with_call_chain'
/Users/pma/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201:in`mon_synchronize'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/task.rb:144:in`invoke'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:112:in `invoke_task'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:90:in`block (2 levels) in top_level'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:90:in `each'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:90:in`block in top_level'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:84:in`top_level'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:62:in `block in run'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:129:in`standard_exception_handling'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/lib/rake/application.rb:59:in `run'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/gems/rake-0.9.2/bin/rake:32:in`<top (required)>'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in `load'
/Users/pma/.rvm/gems/ruby-1.9.2-p290/bin/rake:19:in`<main>'
Tasks: TOP => db:data:load

Gemfile.lock

GIT
  remote: git://github.com/jeanmartin/paperclip.git
  revision: 4095e07adaace2a123cbd031fa268928f3b0ce87
  specs:
    paperclip (2.3.10)
      activerecord (>= 2.3.0)
      activesupport (>= 2.3.2)

GEM
  remote: http://rubygems.org/
  specs:
    Saikuro (1.1.0)
    abstract (1.0.0)
    actionmailer (3.0.10)
      actionpack (= 3.0.10)
      mail (~> 2.2.19)
    actionpack (3.0.10)
      activemodel (= 3.0.10)
      activesupport (= 3.0.10)
      builder (~> 2.1.2)
      erubis (~> 2.6.6)
      i18n (~> 0.5.0)
      rack (~> 1.2.1)
      rack-mount (~> 0.6.14)
      rack-test (~> 0.5.7)
      tzinfo (~> 0.3.23)
    activemodel (3.0.10)
      activesupport (= 3.0.10)
      builder (~> 2.1.2)
      i18n (~> 0.5.0)
    activerecord (3.0.10)
      activemodel (= 3.0.10)
      activesupport (= 3.0.10)
      arel (~> 2.0.10)
      tzinfo (~> 0.3.23)
    activeresource (3.0.10)
      activemodel (= 3.0.10)
      activesupport (= 3.0.10)
    activesupport (3.0.10)
    acts_as_audited (2.0.0.rc7)
      rails (>= 3.0.3)
    addressable (2.2.6)
    arel (2.0.10)
    bcrypt-ruby (2.1.4)
    builder (2.1.2)
    capistrano (2.8.0)
      highline
      net-scp (>= 1.0.0)
      net-sftp (>= 2.0.0)
      net-ssh (>= 2.0.14)
      net-ssh-gateway (>= 1.1.0)
    capybara (1.0.1)
      mime-types (>= 1.16)
      nokogiri (>= 1.3.3)
      rack (>= 1.0.0)
      rack-test (>= 0.5.4)
      selenium-webdriver (~> 2.0)
      xpath (~> 0.1.4)
    capybara-webkit (0.6.0)
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      chronic (>= 0.2.3)
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      builder (>= 2.1.2)
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    cucumber-rails (1.0.2)
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      Saikuro (>= 1.1.0)
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      rack (>= 1.0.0)
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      rack (>= 1.0)
    rails (3.0.10)
      actionmailer (= 3.0.10)
      actionpack (= 3.0.10)
      activerecord (= 3.0.10)
      activeresource (= 3.0.10)
      activesupport (= 3.0.10)
      bundler (~> 1.0)
      railties (= 3.0.10)
    rails_best_practices (0.10.1)
      activesupport
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      erubis
      haml
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      rack (>= 1.0)
    xpath (0.1.4)
      nokogiri (~> 1.3)
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PLATFORMS
  ruby

DEPENDENCIES
  acts_as_audited (= 2.0.0.rc7)
  capistrano
  capybara
  capybara-webkit
  cucumber
  cucumber-rails
  database_cleaner
  devise
  escape_utils
  factory_girl
  factory_girl_rails
  google_currency
  growl
  haml
  jquery-rails
  json
  launchy
  memcache
  memcache-client
  meta_where
  metric_fu
  mime-types
  money
  paperclip!
  pg
  rails (= 3.0.10)
  rb-fsevent
  rspec-rails
  sass
  shoulda
  warden
  yaml_db

[wejrowski]

So I had figured it out earlier. Syck was the answer. Try placing in this in your boot.rb file on local or dev:

YAML::ENGINE.yamler= 'syck'

[fivetwentysix]

Yeah, the 'syck' thing doesn't work for me.

[dimitarvp]

And plus, isn't there a test suite for testing a reference implementation of YAML? How about not releasing incompatible software (as Psych mostly turns out to be)? :-(

[bricestacey]

I had this same problem and it was solved by using syck.

[tleach]

I had this problem too and "worked around" it by simply ensuring all of my tables contained at least a single record before dumping them. It's somewhat inconvenient though...

[kalabiyau]

i my case bug is confirmed like in @tomtheguvnor 's situation.
If in source db there is some blank table - load on destination will fail with syck and psych both

[dnrce]

This is the same error as in #17.