NoMethodError with rake db:migrate

Hi! First of all, this is my first application on Rails, and i’m stuck at a migration. i created a demo app (the demo_app from michael hartl’s tutorial) as usual: rails new demo_app, rails generate scaffold User name:string email:string, and when i do rake db:migrate, this stack appears:

rake db:migrate --trace
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config (first_time)
** Execute db:load_config
** Execute db:migrate
rake aborted!
NoMethodError: undefined method to_a' for #<SQLite3::Statement:0x9d6a2dc>: SELECT name FROM sqlite_master WHERE type = 'table' AND NOT name = 'sqlite_sequence' AND name = "schema_migrations" /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/sqlite_adapter.rb:248:in block in exec_query’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract_adapter.rb:280:in block in log' /var/lib/gems/1.9.1/gems/activesupport-3.2.8/lib/active_support/notifications/instrumenter.rb:20:in instrument’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract_adapter.rb:275:in log' /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/sqlite_adapter.rb:242:in exec_query’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/sqlite_adapter.rb:335:in tables' /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/sqlite_adapter.rb:341:in table_exists?’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/connection_adapters/abstract/schema_statements.rb:425:in initialize_schema_migrations_table' /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/migration.rb:663:in initialize’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/migration.rb:570:in new' /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/migration.rb:570:in up’
/var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/migration.rb:551:in migrate' /var/lib/gems/1.9.1/gems/activerecord-3.2.8/lib/active_record/railties/databases.rake:153:in block (2 levels) in <top (required)>’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in call' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:205:in block in execute’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in each' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:200:in execute’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:158:in block in invoke_with_call_chain' /usr/lib/ruby/1.9.1/monitor.rb:211:in mon_synchronize’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:151:in invoke_with_call_chain' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/task.rb:144:in invoke’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:116:in invoke_task' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in block (2 levels) in top_level’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in each' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:94:in block in top_level’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in standard_exception_handling' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:88:in top_level’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:66:in block in run' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:133:in standard_exception_handling’
/var/lib/gems/1.9.1/gems/rake-0.9.2.2/lib/rake/application.rb:63:in run' /var/lib/gems/1.9.1/gems/rake-0.9.2.2/bin/rake:33:in <top (required)>’
/usr/local/bin/rake:19:in load' /usr/local/bin/rake:19:in
Tasks: TOP => db:migrate

This is the Gemfile:

source ‘https://rubygems.org

gem ‘rails’, ‘3.2.8’

Bundle edge Rails instead:

gem ‘rails’, :git => ‘git://github.com/rails/rails.git

gem ‘sqlite3’
gem ‘sqlite3-ruby’, ‘1.2.5’, :require => ‘sqlite3’

Gems used only for assets and not required

in production environments by default.

group :assets do
gem ‘sass-rails’, ‘~> 3.2.3’
gem ‘coffee-rails’, ‘~> 3.2.1’

See https://github.com/sstephenson/execjs#readme for more supported runtimes

gem ‘therubyracer’, :platforms => :ruby

You need to uncomment the rubyracer to make it work.

Hope this helps.