通过Mongoose更新包含空字段的文档

const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost/mydatabase', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => {
    console.log('Connected to MongoDB');
  })
  .catch((error) => {
    console.error('Error connecting to MongoDB', error);
  });

const mySchema = new mongoose.Schema({
  field1: String,
  field2: Number,
  field3: String
});

const MyModel = mongoose.model('MyModel', mySchema);

MyModel.updateOne({ _id: 'documentId' }, { $set: { field1: 'new value', field2: 42, field3: '' } })
  .then(() => {
    console.log('Document updated successfully');
  })
  .catch((error) => {
    console.error('Error updating document', error);
  });