Model.findById()

Parameters

• id «Any» value of _id to query by

• [projection] «Object|String|Array<String>» optional fields to return, see Query.prototype.select()

• [options] «Object» optional see Query.prototype.setOptions()

• [callback] «Function»

Returns:

• «Query»

Finds a single document by its _id field. findById(id) is almost* equivalent to findOne({ _id: id }). If you want to query by a document’s _id, use findById() instead of findOne().

The id is cast based on the Schema before sending the command.

This function triggers the following middleware.

• findOne()

* Except for how it treats undefined. If you use findOne(), you’ll see that findOne(undefined) and findOne({ _id: undefined }) are equivalent to findOne({}) and return arbitrary documents. However, mongoose translates findById(undefined) into findOne({ _id: null }).

Example:

// Find the adventure with the given `id`, or `null` if not found
await Adventure.findById(id).exec();
// using callback
Adventure.findById(id, function (err, adventure) {});
// select only the adventures name and length
await Adventure.findById(id, 'name length').exec();