insert
Definition
insert
The
insert
command inserts one or more documents and returns a document containing the status of all inserts. The insert methods provided by the MongoDB drivers use this command internally.Tip
In
mongosh
, this command can also be run through thedb.collection.insertOne()
anddb.collection.insertMany()
helper methods.Helper methods are convenient for
mongosh
users, but they may not return the same level of information as database commands. In cases where the convenience is not needed or the additional return fields are required, use the database command.Returns: A document that contains the status of the operation. See Output for details.
Syntax
The command has the following syntax:
db.runCommand( { insert: <collection>, documents: [ <document>, <document>, <document>, ... ], ordered: <boolean>, writeConcern: { <write concern> }, bypassDocumentValidation: <boolean>, comment: <any> } )
Command Fields
The command takes the following fields:
Field | Type | Description |
---|---|---|
insert | string | The name of the target collection. |
documents | array | An array of one or more documents to insert into the named collection. |
ordered | boolean | Optional. If true , then when an insert of a document fails, return without
inserting any remaining documents listed in the inserts array. If
false , then when an insert of a document fails, continue to insert the
remaining documents. Defaults to true . |
writeConcern | document | Optional. A document that expresses the write concern
of the Do not explicitly set the write concern for the operation if run in a transaction. To use write concern with transactions, see Transactions and Write Concern. |
bypassDocumentValidation | boolean | Optional. Enables insert to bypass document validation
during the operation. This lets you insert documents that do not
meet the validation requirements. |
comment | any | Optional. A user-provided comment to attach to this command. Once set, this comment appears alongside records of this command in the following locations:
A comment can be any valid BSON type (string, integer, object, array, etc). New in version 4.4. |
Behavior
Size Limit
The total size of all the documents
array elements must be less
than or equal to the maximum BSON document size.
The total number of documents in the documents
array must be less
than or equal to the maximum bulk size.
Document Validation
The insert
command adds support for the
bypassDocumentValidation
option, which lets you bypass
document validation when
inserting or updating documents in a collection with validation
rules.
Transactions
insert
can be used inside multi-document transactions.
Important
In most cases, multi-document transaction incurs a greater performance cost over single document writes, and the availability of multi-document transactions should not be a replacement for effective schema design. For many scenarios, the denormalized data model (embedded documents and arrays) will continue to be optimal for your data and use cases. That is, for many scenarios, modeling your data appropriately will minimize the need for multi-document transactions.
For additional transactions usage considerations (such as runtime limit and oplog size limit), see also Production Considerations.
Collection Creation in Transactions
Starting in MongoDB 4.4, you can create collections and indexes inside a multi-document transaction if the transaction is not a cross-shard write transaction.
Specifically, in MongoDB 4.4 and greater, if you specify an insert on a non-existing collection in a transaction, the collection is implicitly created.
In MongoDB 4.4 and earlier, the operation must be run on an existing collection.
Write Concerns and Transactions
Do not explicitly set the write concern for the operation if run in a transaction. To use write concern with transactions, see Transactions and Write Concern.
Insert Inaccuracies
Even if you encounter a server error during an insert, some documents may have been inserted.
After a successful insert, the system returns insert.n
, the number
of documents inserted into the collection. If the insert
operation is interrupted by a replica set state change,
the system may continue inserting documents. As a result,
insert.n
may report fewer documents than actually inserted.
Examples
Insert a Single Document
Insert a document into the users
collection:
db.runCommand( { insert: "users", documents: [ { _id: 1, user: "abc123", status: "A" } ] } )
The returned document shows that the command successfully inserted a document. See Output for details.
{ "ok" : 1, "n" : 1 }
Bulk Insert
Insert three documents into the users
collection:
db.runCommand( { insert: "users", documents: [ { _id: 2, user: "ijk123", status: "A" }, { _id: 3, user: "xyz123", status: "P" }, { _id: 4, user: "mop123", status: "P" } ], ordered: false, writeConcern: { w: "majority", wtimeout: 5000 } } )
The returned document shows that the command successfully inserted the three documents. See Output for details.
{ "ok" : 1, "n" : 3 }
Using Insert with bypassDocumentValidation
If schema validation validationActions
are set to error
, inserts to a collection return errors for
documents that violate the schema validation rules. To insert documents
which would violate these rules set bypassDocumentValidation: true
.
Create the user
collection with a validation rule on the status
fields.
The validation rule validates that the status must be "Unknown" or "Incomplete":
db.createCollection("users", { validator: { status: { $in: [ "Unknown", "Incomplete" ] } } })
Attempt to insert a document which violates the validation rule:
db.runCommand({ insert: "users", documents: [ {user: "123", status: "Active" } ] })
The insert returns a write error message:
{ n: 0, writeErrors: [ { index: 0, code: 121, errInfo: { failingDocumentId: ObjectId('6197a7f2d84e85d1cc90d270'), details: { operatorName: '$in', specifiedAs: { status: { '$in': [Array] } }, reason: 'no matching value found in array', consideredValue: 'Active' } }, errmsg: 'Document failed validation' } ], ok: 1 }
Set bypassDocumentValidation : true
and rerun the insert:
db.runCommand({ insert: "users", documents: [ {user: "123", status: "Active" } ], bypassDocumentValidation: true })
The operation succeeds.
To check for documents that violate schema validation rules, use the
validate
command.
Output
The returned document contains a subset of the following fields:
insert.writeErrors
An array of documents that contains information regarding any error encountered during the insert operation. The
writeErrors
array contains an error document for each insert that errors.Each error document contains the following fields:
insert.writeConcernError
Document that describe error related to write concern and contains the field:
insert.writeConcernError.errInfo.writeConcern
New in version 4.4.
The write concern object used for the corresponding operation. For information on write concern object fields, see Write Concern Specification.
The write concern object may also contain the following field, indicating the source of the write concern:
insert.writeConcernError.errInfo.writeConcern.provenance
A string value indicating where the write concern originated (known as write concern
provenance
). The following table shows the possible values for this field and their significance:ProvenanceDescriptionclientSupplied
The write concern was specified in the application.customDefault
The write concern originated from a custom defined default value. SeesetDefaultRWConcern
.getLastErrorDefaults
The write concern originated from the replica set'ssettings.getLastErrorDefaults
field.implicitDefault
The write concern originated from the server in absence of all other write concern specifications.
The following is an example document returned for a successful
insert
of a single document:
{ ok: 1, n: 1 }
The following is an example document returned for an
insert
of two documents that successfully inserted one
document but encountered an error with the other document:
{ "ok" : 1, "n" : 1, "writeErrors" : [ { "index" : 1, "code" : 11000, "errmsg" : "insertDocument :: caused by :: 11000 E11000 duplicate key error index: test.users.$_id_ dup key: { : 1.0 }" } ] }