Best way to create a View from these two collections

Working with Data
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2

@Martin_Koslof I recommend using the “aggregate” method with the “$lookup” stage to join the collections based on a matching field. You can then use other stages such as “$project” or “$group” to shape the output of the view as needed. Here is an example of how to create a view from two collections:

db.createView("myView", "collection1", [
 {
   $lookup: {
     from: "collection2",
     localField: "commonField",
     foreignField: "commonField",
     as: "joinedData"
   }
 },
 {
   $unwind: {
     path: "$joinedData",
     preserveNullAndEmptyArrays: true
   }
 }
])

In the above example, the “myView” view is being created based on “collection1”. The “$lookup” stage is used to join “collection1” with “collection2” based on a common field called “commonField”. The resulting documents are then flattened using “$unwind” to create one document per matching pair of documents from the two collections.
Note that in order to create a view in MongoDB, you must have the “createView” privilege on the database.

Hope this was helpful :slight_smile: