You have an e-commerce database with two collections: orders (each order document has an array field productIds) and products (each product document has _id as the product ID and other details). You want an aggregation pipeline that, for each order, outputs a separate document for each product in that order, including the product’s details. Which of the following pipelines achieves this?

Question

Answer

db.products.aggregate([ { $unwind: "$productIds" }, { $lookup: { from: "orders", localField: "_id", foreignField: "productIds", as: "orderInfo" }} ])

Answer

db.orders.aggregate([ { $unwind: "$productIds" }, { $lookup: { from: "products", localField: "_id", foreignField: "productIds", as: "productInfo" }} ])

0%

Answer

db.orders.aggregate([ { $unwind: "$productIds" }, { $lookup: { from: "products", localField: "productIds", foreignField: "_id", as: "productInfo" }} ])

Answer

db.orders.aggregate([ { $lookup: { from: "products", localField: "productIds", foreignField: "_id", as: "productInfo" }} ])

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You have an e-commerce database with two collections: orders (each order docu...

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