how to update mongodb with two field-CodePudding

db.auto_complete.find()

{ "_id" : ObjectId("6239a3c93a8e84c1b46d1bf4"), "category" : "음식", "keyword" : "삼겹살", "weight" : 0, "shard" : 5, "searchCount" : 3, "satisfactionCount" : 4, "force" : false }

but i want to update weight = (searchCount X 0.5 satisfactionCount X 0.5)

my wanted result =

{ "_id" : ObjectId("6239a3c93a8e84c1b46d1bf4"), "category" : "음식", "keyword" : "삼겹살", "weight" : 3, "shard" : 5, "searchCount" : 3, "satisfactionCount" : 4, "force" : false }

weight = ( 3(searchCount)X0.5 4(satisfactionCount)X0.5 ) =>3.5 ( round off) => 3

i have tried with $set but i didn't solved this problem how to query this problem with mongo and if weight have decimal point i want round off the decimal point please help me....

CodePudding user response：

Maybe something like this:

db.collection.update({},
[
 {
   $addFields: {
  // weight = (searchCount X 0.5   satisfactionCount X 0.5)
    weight: {
     $trunc: [
      {
        "$sum": [
          {
            "$multiply": [
              "$searchCount",
              0.5
            ]
          },
          {
            "$multiply": [
              "$satisfactionCount",
              0.5
            ]
          }
        ]
       },
      0
     ]
     }
    }
  }
],{multi:true})

Explained:

Use the the update with aggregation pipeline method ( mongodb 4.2 ) to replace the weight value with the rounded calculated based on provided formula. Add the option { multi:true } to apply to all documents in the collection.

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