how to save in mongoose code example

Example 1: mongoose save method

var Tank = mongoose.model('Tank', yourSchema);

var small = new Tank({ size: 'small' });
small.save(function (err) {
  if (err) return handleError(err);
  // saved!
});

// or

Tank.create({ size: 'small' }, function (err, small) {
  if (err) return handleError(err);
  // saved!
});

// or, for inserting large batches of documents
Tank.insertMany([{ size: 'small' }], function(err) {

});

Example 2: mongoose save a document

const Person = mongoose.model('Person', Schema({
  name: String,
  rank: String
}));

const doc = new Person({
  name: 'Will Riker',
  rank: 'Commander'
});
// Inserts a new document with `name = 'Will Riker'` and
// `rank = 'Commander'`
await doc.save();

const person = await Person.findOne();
person.name; // 'Will Riker'