Mongoose，如果找到更新，则创建

Question

Ok so,lets say i have this array :

const names = ["john","bill","mark"]

and this Model :

const namesSchema = new Schema({
  name: String,
  frequency: Number,
});

I want to search each one of the array items by name,and if it exists,simply increment the frequency number by 1,else create the document with a name:array_item and frequency:1

I know i could just forEach the array,and do something like the following for each name :

names.forEach(i => {
  const name_doc = await namesSchema.findOne({
    name: i,
  });
  if (name_doc) {
    name_doc.frequency += 1;
    name_doc.save()
  } else {
    const new_name_doc = new namesSchema({
      name: i,
      frequency: 1,
    });
    new_name_doc.save()
  }
})

but i was wondering if there is a more cohesive method where i could just pass the array,and the update function with an upsert option that does all this logic with a single call with no iterations

Answer 1

This might help you.

I start with the collection

[
    { "name": "mark" },
    { "name": "bill" },
    { "name": "john" }
]

and use this query to addnew docuemnt or increte frequence by name

db.collection.update({name:'mark'},{$inc:{"frequence":1}},{upsert:true})

---

Edit

or pass the array to query

const names = ["john", "bill", "mark"]

var updates= names.map(function(item) {
    return {
        "updateOne": {
            "filter": { name: item },
            "update": { $inc: { "frequence": 1 } },
            "upsert": true
        }
    };
});

db.collection.bulkWrite(updates, {})

or

const names = ["john", "bill", "mark"]
    
names.map(function(item){
    db.collection.update({ name: item }, { $inc: { "frequence": 1 } }, { upsert: true })
})