Redmine/issue_relations/lib/tasks/extract_fixtures.rake

desc 'Create YAML test fixtures from data in an existing database.
Defaults to development database. Set RAILS_ENV to override.'

task :extract_fixtures => :environment do
  sql = "SELECT * FROM %s"
  skip_tables = ["schema_info"]
  ActiveRecord::Base.establish_connection
  (ActiveRecord::Base.connection.tables - skip_tables).each do |table_name|
    i = "000"
    File.open("#{RAILS_ROOT}/#{table_name}.yml", 'w' ) do |file|
      data = ActiveRecord::Base.connection.select_all(sql % table_name)
      file.write data.inject({}) { |hash, record|
      
      # cast extracted values
      ActiveRecord::Base.connection.columns(table_name).each { |col|
        record[col.name] = col.type_cast(record[col.name]) if record[col.name]      
      }      
      
      hash["#{table_name}_#{i.succ!}"] = record
      hash
      }.to_yaml
    end
  end
end