Product Catalog with MongoDB - price model

Question

I followed Product Catalog with MongoDB, Part 1: Schema Design but i'm not sure how to use it.

My question is how to retrieve products in a specific category with their prices?(like a simple category page in an e-commerce website)

• If i put prices in the same collection with products (embed it in the product model) so with a single query i can get price for each product but i don't have as flexibility as second approach(for example variant pricing is impossible).

  sample product document:

  {
      id: '054VA72303012P',
      name: 'women's kate ivory',
         ...
      prices: [{
              val: 127788.33,
              startDate: '2018-12-31 23:59:59',
              endDate: '2019-2-31 23:59:59',
              }]
  }
  

• Second option is to store prices as a separate collection (as it said in the article). But i'm wondering how to retrieve products with their prices. Is it possible to do that with a single query? as MongoDB doesn't have JOIN operation how should i select a product with the corresponding prices. Sample schemas with complete descriptions are available in the article.

Sample schemas:

    product_document:{
          "_id": '054VA72303012P',
          "name": 'women's kate ivory',
          ...
    }
    variant_document:{
          "_id": "05458452563",
          "itemId": "054VA72303012P",
          "name": "Width:Medium,Color:Ivory,Shoe Size:6.5",
          ...
    }
    price_document:{
          "_id": "054VA72303012P_1234",
          "price": "69.99",
          ...
    }