title: How to manually set createdAt timestamp in mongoDB using mongoose?
body: <p>I am trying to migrate my DB by adding timestamps to all the rows which were missing timestamps earlier. I have calculated createdAt timestamp using _id but I'm not able to set the timestamp. What am I doing wrong here?
  Can someone help?</p>
  
  <pre><code>    let Question = db.model('Question');
  
      let items = await Question.findWithDeleted();
  
      let processedIds = items.map((q) =&gt; q._id);
      processedIds.forEach(function (id) {
  
          const timestamp = id.getTimestamp();
  
          // const date = new Date(parseInt(timestamp, 16) * 1000);
          // echo(timestamp)
          Question.update({ "_id": id }, { "$set": { createdAt: timestamp } }, (h) =&gt; {
              console.log(h);
          });
  
      });
  </code></pre>
  
  <p>Here is the model:</p>
  
  <pre>
  
      const Question = new Schema({
          "type": {
              type: String,
              trim: true,
              enum: Object.values(questionTypes),
              required: 'Question type is required'
          },
          "text": {
              type: String,
              required: true
          },
          "desc": NotRequiredStringSchema,
          "options": [{
              "id": ObjectId,
              "name": NotRequiredStringSchema,
              "helperText": NotRequiredStringSchema,
              "icon_key": NotRequiredStringSchema,
              "icon_url": NotRequiredStringSchema,
              "icon_svg": NotRequiredStringSchema
          }],
          "placeHolder": NotRequiredStringSchema,
          "buttonPosition": NotRequiredStringSchema,
          "buttonText": NotRequiredStringSchema,
          "buttonHoverText": NotRequiredStringSchema,
          "helperText": NotRequiredStringSchema,
          "max": Number,
          "min": Number,
          "default": Mixed,
          "icon_key": NotRequiredStringSchema,
          "icon_url": NotRequiredStringSchema,
          "icon_svg": NotRequiredStringSchema,
          "showTick": { type: Boolean, required: false, default: false },
          "lang": {
              required: true,
              type: Map,
              of: {
                  type: Map,
                  of: String
              }
          }
      }, {
              timestamps: true
          });
  
  </pre>