Check out example codes for "mongo object references in mongoose". It will help you in understanding the concepts better.
Code Example 1
User = new Schema({
places:[{type: Schema.Types.ObjectId, ref:'Place'}],
shouts:[{type: Schema.Types.ObjectId, ref:'Shout'}]
});
Place = new Schema({
name:String,
description:String,
});
Shout = new Schema({
content:String,
});
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