title: Mongoose Schema, how to nest objects in one schema?
body: <p>In my mongoose schema, I have defined some data types and two object array.
  The first object dish which should be ok. </p>
  
  <p>But in the second nested object order I want to include the first object dish into and I do not know the way to do this properly.     </p>
  
  <pre><code>module.exports = function( mongoose) {
        var ShopSchema = new mongoose.Schema({
          shopName:     { type: String, unique: true },
          address:     { type: String},
          location:{type:[Number],index: '2d'},
          shopPicUrl:      {type: String},
          shopPicTrueUrl:{type: String},
          mark:  { type: String},
          open:{type:Boolean},
          shopType:{type:String},
  
          dish:   {type: [{
            dishName: { type: String},
            tags: { type: Array},
            price: { type: Number},
            intro: { type: String},
            dishPic:{ type: String},
            index:{type:Number},
            comment:{type:[{
              date:{type: Date,default: Date.now},
              userId:{type: String},
              content:{type: String}
            }]}
          }]},
  
          order:{type:[{
            orderId:{type: String},
            date:{type: Date,default: Date.now},
            dish:{type: [dish]},//!!!!!!!!! could I do this?
            userId:{type: String}
          }]}
  
        });
  </code></pre>