Every catalog application supports an image or set of images bound to this item. For that purpose, in the next chapter, we will see how to work with binary objects in MongoDB. However, now is the time to decide how to semantically link the binary data to an item document. Extending the model schema in such a way that it contains binary base64 representation of binary data in the document is anything but a good idea, as mixing literally encoded and binary data in one format is never a good idea. It increases the complexity of the application and makes it error-prone:

{
  "_id": "5a4c004b0eed73835833cc9a",
  "itemId": "1",
  "itemName": "Sports Watch",
  "price": 100,
  "currency": "EUR",
  "categories": [
    "Watches",
    "Sports Watches"
  ],
  "image":" 
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...