查询嵌套对象mongoose

Question

我有这个架构：

let answersSchema = new mongoose.Schema({
    answerId: {
        type: Number,
        required: true
    },
    answerTitle: {
        type: String,
        required: true
    }
});

let individualQuestionsSchema = new mongoose.Schema({
    questionId: {
        type: Number,
        required: true
    },
    type: {
        type: String,
        required: true
    },
    questionTitle: {
        type: String,
        required: true
    },
    answers: [answersSchema]
});


let questionSchema = new mongoose.Schema({
    questions: [individualQuestionsSchema]

});

使用mongoose我想查询我的集合中的所有数据。当我执行：

QuestionMongo.findOne().exec((err, res) => {
                logger.debug(res);
        });

这是输出：

    { 
       _id: 5948eec705bb435feafb0d48,
       questions: 
       [ 
           { 
               questionId: 1,
               questionTitle: 'Question01',
               answerType: 'radio',
               answers: [Object] 
           },
           { 
               questionId: 2,
               questionTitle: 'Question02',
               answerType: 'radio',
               answers: [Object] 
           } 
        ] 
     }

为什么出现[对象]而不是它应该显示的内容？