10818776.js

var mongoose = require('./../mongoose');
var Schema = mongoose.Schema;
mongoose.connect('localhost', 'testing_10818776');
mongoose.connection.on('error', function () {
  console.error(arguments);
});

var schema = new Schema({
    name: String
  , msg: [new Schema({ isRead: Boolean })]
});

var A = mongoose.model('A', schema);

mongoose.connection.on('open', function () {
  var a = new A;
  a.name = 'test'
  a.msg = [{isRead: false}]
  a.save(function (err, a) {
    if (err) return console.error(err.stack||err);

    A.findById(a, function (err, doc) {
      if (err) console.error(err.stack||err);
      console.error('found', doc);

      doc.msg.forEach(function (doc) {
        doc.isRead = true;
      });

      doc.save(function (err) {
        if (err) console.error(err.stack||err);

        A.findById(a, function (err, doc) {
          if (err) console.error(err.stack||err);
          console.error('result', doc);
          mongoose.connection.db.dropDatabase(function () {
            mongoose.connection.close();
          });
        });
      });

    });
  })
});