Sequence support in PostgreSQL

001_postgresql_adapter_patches.rb

require 'active_record/base'
require 'active_record/connection_adapters/abstract_adapter'
require 'active_record/connection_adapters/postgresql_adapter'

module ActiveRecord
  module ConnectionAdapters
    class PostgreSQLAdapter < AbstractAdapter
      def next_sequence_value(sequence_name)
        Integer(select_value("SELECT NEXTVAL('#{sequence_name}')"))
      end
      
      def prefetch_primary_key?(table_name)
        true
      end
    end
  end
end