Insert Documents
This page provides examples of insert operations in MongoDB.
CREATING A COLLECTION
If the collection does not currently exist, insert operations will create the collection.
Insert a Single Document
New in version 3.2.
Collection.insertOne()inserts asingledocumentinto a collection.
The following example inserts a new document into theinventory
collection. If the document does not specify an_id
field, the Node.js driver adds the_id
field with an ObjectId value to the new document. SeeInsert Behavior.
db.collection('inventory').insertOne({
item: "canvas",
qty: 100,
tags: ["cotton"],
size: { h: 28, w: 35.5, uom: "cm" }
})
.then(function(result) {
// process result
})
insertOne()returns a promise that provides aresult
. Theresult.insertedId
promise contains the_id
of the newly inserted document.
To retrieve the document that you just inserted,query the collection:
var cursor = db.collection('inventory').find({
item: "canvas",
});
Insert Multiple Documents
New in version 3.2.
Collection.insertMany()can insertmultipledocumentsinto a collection. Pass an array of documents to the method.
The following example inserts three new documents into theinventory
collection. If the documents do not specify an_id
field, the Node.js driver adds the_id
field with an ObjectId value to each document. SeeInsert Behavior.
db.collection('inventory').insertMany([
{ item: "journal",
qty: 25,
tags: ["blank", "red"],
size: { h: 14, w: 21, uom: "cm" }},
{ item: "mat",
qty: 85,
tags: ["gray"],
size: { h: 27.9, w: 35.5, uom: "cm" }},
{ item: "mousepad",
qty: 25,
tags: ["gel", "blue"],
size: { h: 19, w: 22.85, uom: "cm" }}
])
.then(function(result) {
// process result
})
insertMany()returns a promise that provides aresult
. Theresult.insertedIds
field contains an array with the_id
of each newly inserted document.
To retrieve the inserted documents,query the collection:
var cursor = db.collection('inventory').find({});
Insert Behavior
Collection Creation
If the collection does not currently exist, insert operations will create the collection.
_id
Field
In MongoDB, each document stored in a collection requires a unique_idfield that acts as aprimary key. If an inserted document omits the_id
field, the MongoDB driver automatically generates anObjectIdfor the_id
field.
This also applies to documents inserted through update operations withupsert: true.
Atomicity
All write operations in MongoDB are atomic on the level of a single document. For more information on MongoDB and atomicity, seeAtomicity and Transactions
Write Acknowledgement
With write concerns, you can specify the level of acknowledgement requested from MongoDB for write operations. For details, seeWrite Concern.
SEE ALSO