way to update multiple documents with different values

Question

I have the following documents:

[{
  \"_id\":1,
  \"name\":\"john\",
  \"position\":1
},
 {\"_id\":2,
  \"name\":\"bob\",
  \"position\":2
},
 {\"_id\":3,
           


        

Answer 1

From mongodb 4.2 you can do using pipeline in update using $set operator

there are many ways possible now due to many operators in aggregation pipeline though I am providing one of them

    exports.updateDisplayOrder = async keyValPairArr => {
    try {
        let data = await ContestModel.collection.update(
            { _id: { $in: keyValPairArr.map(o => o.id) } },
            [{
                $set: {
                    displayOrder: {
                        $let: {
                            vars: { obj: { $arrayElemAt: [{ $filter: { input: keyValPairArr, as: "kvpa", cond: { $eq: ["$$kvpa.id", "$_id"] } } }, 0] } },
                            in:"$$obj.displayOrder"
                        
                        }
                    }
                }
            }],
            { runValidators: true, multi: true }
        )

        return data;
    } catch (error) {
        throw error;
    }
   }

example key val pair is [{"id":"5e7643d436963c21f14582ee","displayOrder":9}, {"id":"5e7643e736963c21f14582ef","displayOrder":4}]