db.collection.updateOne()

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Definition

Compatibility
Syntax
Access Control
Behavior
Examples

MongoDB with drivers

This page documents a mongosh method. To see the equivalent method in a MongoDB driver, see the corresponding page for your programming language:

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Definition

db.collection.updateOne(filter, update, options): Updates a single document within the collection based on the filter.

Compatibility

You can use db.collection.updateOne() for deployments hosted in the following environments:

MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud

MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB

Syntax

The updateOne() method has the following syntax:

db.collection.updateOne(
   <filter>,
   <update>,
   {
     upsert: <boolean>,
     writeConcern: <document>,
     collation: <document>,
     arrayFilters: [ <filterdocument1>, ... ],
     hint:  <document|string>,
     let: <document>
   }
)

Parameters

The db.collection.updateOne() method takes the following parameters:

Parameter

Type

Description

filter

document

The selection criteria for the update. The same query selectors as in the find() method are available.

Specify an empty document { } to update the first document returned in the collection.

update

document or pipeline

The modifications to apply. Can be one of the following:

Update document	Contains only update operator expressions. For more information, see Update with an Update Operator Expressions Document
Aggregation pipeline	Contains only the following aggregation stages: `$addFields` and its alias `$set` `$project` and its alias `$unset` `$replaceRoot` and its alias `$replaceWith`. For more information, see Update with an Aggregation Pipeline.

To update with a replacement document, see db.collection.replaceOne().

upsert

boolean

Optional. When true, updateOne() either:

Creates a new document if no documents match the filter. For more details see upsert behavior.
Updates a single document that matches the filter.

To avoid multiple upserts, ensure that the filter field(s) are uniquely indexed.

Defaults to false, which does not insert a new document when no match is found.

writeConcern

document

Optional. A document expressing the write concern. Omit to use the default write concern.

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.

collation

document

Optional.

Specifies the collation to use for the operation.

Collation allows users to specify language-specific rules for string comparison, such as rules for lettercase and accent marks.

The collation option has the following syntax:

collation: {
   locale: <string>,
   caseLevel: <boolean>,
   caseFirst: <string>,
   strength: <int>,
   numericOrdering: <boolean>,
   alternate: <string>,
   maxVariable: <string>,
   backwards: <boolean>
}

When specifying collation, the locale field is mandatory; all other collation fields are optional. For descriptions of the fields, see Collation Document.

If the collation is unspecified but the collection has a default collation (see db.createCollection()), the operation uses the collation specified for the collection.

If no collation is specified for the collection or for the operations, MongoDB uses the simple binary comparison used in prior versions for string comparisons.

You cannot specify multiple collations for an operation. For example, you cannot specify different collations per field, or if performing a find with a sort, you cannot use one collation for the find and another for the sort.

arrayFilters

array

Optional. An array of filter documents that determine which array elements to modify for an update operation on an array field.

In the update document, use the $[<identifier>] filtered positional operator to define an identifier, which you then reference in the array filter documents. You cannot have an array filter document for an identifier if the identifier is not included in the update document.

Note

The <identifier> must begin with a lowercase letter and contain only alphanumeric characters.

You can include the same identifier multiple times in the update document; however, for each distinct identifier ($[identifier]) in the update document, you must specify exactly one corresponding array filter document. That is, you cannot specify multiple array filter documents for the same identifier. For example, if the update statement includes the identifier x (possibly multiple times), you cannot specify the following for arrayFilters that includes 2 separate filter documents for x:

// INVALID
[
  { "x.a": { $gt: 85 } },
  { "x.b": { $gt: 80 } }
]

However, you can specify compound conditions on the same identifier in a single filter document, such as in the following examples:

// Example 1
[
  { $or: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] }
]
// Example 2
[
  { $and: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] }
]
// Example 3
[
  { "x.a": { $gt: 85 }, "x.b": { $gt: 80 } }
]

For examples, see Specify arrayFilters for an Array Update Operations.

hint

Document or string

Optional. A document or string that specifies the index to use to support the query predicate.

The option can take an index specification document or the index name string.

If you specify an index that does not exist, the operation errors.

For an example, see Specify hint for Update Operations.

let

Document

Optional.

Specifies a document with a list of variables. This allows you to improve command readability by separating the variables from the query text.

The document syntax is:

{
  <variable_name_1>: <expression_1>,
  ...,
  <variable_name_n>: <expression_n>
}

The variable is set to the value returned by the expression, and cannot be changed afterwards.

To access the value of a variable in the command, use the double dollar sign prefix ($$) together with your variable name in the form $$<variable_name>. For example: $$targetTotal.

Note

To use a variable to filter results, you must access the variable within the $expr operator.

For a complete example using let and variables, see Update with let Variables.

Returns

The method returns a document that contains:

matchedCount containing the number of matched documents
modifiedCount containing the number of modified documents
upsertedId containing the _id for the upserted document
upsertedCount containing the number of upserted documents
A boolean acknowledged as true if the operation ran with write concern or false if write concern was disabled

Access Control

On deployments running with authorization, the user must have access that includes the following privileges:

update action on the specified collection(s).
find action on the specified collection(s).
insert action on the specified collection(s) if the operation results in an upsert.

The built-in role readWrite provides the required privileges.

Behavior

Updates a Single Document

db.collection.updateOne() finds the first document that matches the filter and applies the specified update modifications.

Update with an Update Operator Expressions Document

For the update specifications, the db.collection.updateOne() method can accept a document that only contains update operator expressions.

For example:

db.collection.updateOne(
   <query>,
   { $set: { status: "D" }, $inc: { quantity: 2 } },
   ...
)

Update with an Aggregation Pipeline

The db.collection.updateOne() method can accept an aggregation pipeline [ <stage1>, <stage2>, ... ] that specifies the modifications to perform. The pipeline can consist of the following stages:

$addFields and its alias $set
$project and its alias $unset
$replaceRoot and its alias $replaceWith.

Using the aggregation pipeline allows for a more expressive update statement, such as expressing conditional updates based on current field values or updating one field using the value of another field(s).

For example:

db.collection.updateOne(
   <query>,
   [
      { $set: { status: "Modified", comments: [ "$misc1", "$misc2" ] } },
      { $unset: [ "misc1", "misc2" ] }
   ]
   ...
)

Note

The $set and $unset used in the pipeline refers to the aggregation stages $set and $unset respectively, and not the update operators $set and $unset.

For examples, see Update with Aggregation Pipeline.

Upsert

Starting in MongoDB 7.1, if you specify upsert: true on a sharded collection, you do not need to include the full shard key in the filter.
If upsert: true and no documents match the filter, db.collection.updateOne() creates a new document based on the filter criteria and update modifications. See Update with Upsert.
For additional db.collection.updateOne() behavior on a sharded collection, see Sharded Collections.

Capped Collection

If an update operation changes the document size, the operation will fail.

Sharded Collections

`upsert` on a Sharded Collection

To use db.collection.updateOne() on a sharded collection:

Starting in MongoDB 7.1, if you specify upsert: true on a sharded collection, you do not need to include the full shard key in the filter.
If you don't specify upsert: true, you must include an exact match on the _id field or target a single shard (such as by including the shard key in the filter).

However, documents in a sharded collection can be missing the shard key fields. To target a document that is missing the shard key, you can use the null equality match in conjunction with another filter condition (such as on the _id field). For example:

{ _id: <value>, <shardkeyfield>: null } // _id of the document missing shard key

Shard Key Modification

You can update a document's shard key value unless the shard key field is the immutable _id field.

Warning

Documents in sharded collections can be missing the shard key fields. Take precaution to avoid accidentally removing the shard key when changing a document's shard key value.

To modify the existing shard key value with db.collection.updateOne():

You must run on a mongos. Do not issue the operation directly on the shard.
You must run either in a transaction or as a retryable write.
You must include an equality filter on the full shard key.

Missing Shard Key

Starting in version 7.1, you do not need to provide the shard key or _id field in the query specification.

Documents in a sharded collection can be missing the shard key fields. To use db.collection.updateOne() to set a missing shard key, you must run on a mongos. Do not issue the operation directly on the shard.

In addition, the following requirements also apply:

Task	Requirements
To set to `null`	Requires equality filter on the full shard key if `upsert: true`.
To set to a non-`null` value	Must be performed either inside a transaction or as a retryable write. Requires equality filter on the full shard key if `upsert: true`.

Tip

Since a missing key value is returned as part of a null equality match, to avoid updating a null-valued key, include additional query conditions (such as on the _id field) as appropriate.

Explainability

updateOne() is not compatible with db.collection.explain().

Transactions

db.collection.updateOne() can be used inside distributed transactions.

Important

In most cases, a distributed transaction incurs a greater performance cost over single document writes, and the availability of distributed 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 distributed transactions.

For additional transactions usage considerations (such as runtime limit and oplog size limit), see also Production Considerations.

Upsert within Transactions

You can create collections and indexes inside a distributed transaction if the transaction is not a cross-shard write transaction.

db.collection.updateOne() with upsert: true can be run on an existing collection or a non-existing collection. If run on a non-existing collection, the operation creates the collection.

Tip

Oplog Entries

If a db.collection.updateOne() operation successfully updates a document, the operation adds an entry on the oplog (operations log). If the operation fails or does not find a document to update, the operation does not add an entry on the oplog.

Examples

Update using Update Operator Expressions

The restaurant collection contains the following documents:

{ "_id" : 1, "name" : "Central Perk Cafe", "Borough" : "Manhattan" },
{ "_id" : 2, "name" : "Rock A Feller Bar and Grill", "Borough" : "Queens", "violations" : 2 },
{ "_id" : 3, "name" : "Empire State Pub", "Borough" : "Brooklyn", "violations" : 0 }

The following operation updates a single document where name: "Central Perk Cafe" with the violations field:

try {
   db.restaurant.updateOne(
      { "name" : "Central Perk Cafe" },
      { $set: { "violations" : 3 } }
   );
} catch (e) {
   print(e);
}

The operation returns:

{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }

If no matches were found, the operation instead returns:

{ "acknowledged" : true, "matchedCount" : 0, "modifiedCount" : 0 }

Setting upsert: true would insert the document if no match was found. See Update with Upsert

Update with Aggregation Pipeline

The db.collection.updateOne() can use an aggregation pipeline for the update. The pipeline can consist of the following stages:

$addFields and its alias $set
$project and its alias $unset
$replaceRoot and its alias $replaceWith.

Example 1

The following examples uses the aggregation pipeline to modify a field using the values of the other fields in the document.

Create a students collection with the following documents:

db.students.insertMany( [
   { "_id" : 1, "student" : "Skye", "points" : 75, "commentsSemester1" : "great at math", "commentsSemester2" : "loses temper", "lastUpdate" : ISODate("2019-01-01T00:00:00Z") },
   { "_id" : 2, "student" : "Elizabeth", "points" : 60, "commentsSemester1" : "well behaved", "commentsSemester2" : "needs improvement", "lastUpdate" : ISODate("2019-01-01T00:00:00Z") }
] )

Assume that instead of separate commentsSemester1 and commentsSemester2 fields in the first document, you want to gather these into a comments field, like the second document. The following update operation uses an aggregation pipeline to:

add the new comments field and set the lastUpdate field.
remove the commentsSemester1 and commentsSemester2 fields for all documents in the collection.

Make sure that the filter in the update command targets a unique document. The field id in the code below is an example of such a filter:

db.students.updateOne(
   { _id: 1 },
   [
      { $set: { status: "Modified", comments: [ "$commentsSemester1", "$commentsSemester2" ], lastUpdate: "$$NOW" } },
      { $unset: [ "commentsSemester1", "commentsSemester2" ] }
   ]
)

Note

The $set and $unset used in the pipeline refers to the aggregation stages $set and $unset respectively, and not the update operators $set and $unset.

First Stage

The $set stage:

creates a new array field comments whose elements are the current content of the misc1 and misc2 fields and
sets the field lastUpdate to the value of the aggregation variable NOW. The aggregation variable NOW resolves to the current datetime value and remains the same throughout the pipeline. To access aggregation variables, prefix the variable with double dollar signs $$ and enclose in quotes.

Second Stage

The $unset stage removes the commentsSemester1 and commentsSemester2 fields.

After the command, the collection contains the following documents:

{ "_id" : 2, "student" : "Elizabeth", "status" : "Modified", "points" : 60, "lastUpdate" : ISODate("2020-01-23T05:11:45.784Z"), "comments" : [ "well behaved", "needs improvement" ] }
{ _id: 1, student: 'Skye', points: 75, commentsSemester1: 'great at math', commentsSemester2: 'loses temper', lastUpdate: ISODate("2019-01-01T00:00:00.000Z") }

Note that after introducing a sort, only the first document encountered in the sort order is modified and the remaining documents are left untouched.

Example 2

The aggregation pipeline allows the update to perform conditional updates based on the current field values as well as use current field values to calculate a separate field value.

For example, create a students3 collection with the following documents:

db.students3.insertMany( [
   { "_id" : 1, "tests" : [ 95, 92, 90 ], "average" : 92, "grade" : "A", "lastUpdate" : ISODate("2020-01-23T05:18:40.013Z") },
   { "_id" : 2, "tests" : [ 94, 88, 90 ], "average" : 91, "grade" : "A", "lastUpdate" : ISODate("2020-01-23T05:18:40.013Z") },
   { "_id" : 3, "tests" : [ 70, 75, 82 ], "lastUpdate" : ISODate("2019-01-01T00:00:00Z") }
] )

The third document _id: 3 is missing the average and grade fields. Using an aggregation pipeline, you can update the document with the calculated grade average and letter grade.

db.students3.updateOne(
   { _id: 3 },
   [
     { $set: { average: { $trunc: [  { $avg: "$tests" }, 0 ] }, lastUpdate: "$$NOW" } },
     { $set: { grade: { $switch: {
                           branches: [
                               { case: { $gte: [ "$average", 90 ] }, then: "A" },
                               { case: { $gte: [ "$average", 80 ] }, then: "B" },
                               { case: { $gte: [ "$average", 70 ] }, then: "C" },
                               { case: { $gte: [ "$average", 60 ] }, then: "D" }
                           ],
                           default: "F"
     } } } }
   ]
)

Note

The $set used in the pipeline refers to the aggregation stage $set, and not the update operators $set.

First Stage

The $set stage:

calculates a new field average based on the average of the tests field. See $avg for more information on the $avg aggregation operator and $trunc for more information on the $trunc truncate aggregation operator.
sets the field lastUpdate to the value of the aggregation variable NOW. The aggregation variable NOW resolves to the current datetime value and remains the same throughout the pipeline. To access aggregation variables, prefix the variable with double dollar signs $$ and enclose in quotes.

Second Stage

The $set stage calculates a new field grade based on the average field calculated in the previous stage. See $switch for more information on the $switch aggregation operator.

After the command, the collection contains the following documents:

{ "_id" : 1, "tests" : [ 95, 92, 90 ], "average" : 92, "grade" : "A", "lastUpdate" : ISODate("2020-01-23T05:18:40.013Z") }
{ "_id" : 2, "tests" : [ 94, 88, 90 ], "average" : 91, "grade" : "A", "lastUpdate" : ISODate("2020-01-23T05:18:40.013Z") }
{ "_id" : 3, "tests" : [ 70, 75, 82 ], "lastUpdate" : ISODate("2020-01-24T17:33:30.674Z"), "average" : 75, "grade" : "C" }

Tip

Update with Upsert

The restaurant collection contains the following documents:

{ "_id" : 1, "name" : "Central Perk Cafe", "Borough" : "Manhattan", "violations" : 3 },
{ "_id" : 2, "name" : "Rock A Feller Bar and Grill", "Borough" : "Queens", "violations" : 2 },
{ "_id" : 3, "name" : "Empire State Pub", "Borough" : "Brooklyn", "violations" : "0" }

The following operation attempts to update the document with name : "Pizza Rat's Pizzaria", while upsert: true :

try {
   db.restaurant.updateOne(
      { "name" : "Pizza Rat's Pizzaria" },
      { $set: {"_id" : 4, "violations" : 7, "borough" : "Manhattan" } },
      { upsert: true }
   );
} catch (e) {
   print(e);
}

Since upsert:true the document is inserted based on the filter and update criteria. The operation returns:

{
   "acknowledged" : true,
   "matchedCount" : 0,
   "modifiedCount" : 0,
   "upsertedId" : 4,
   "upsertedCount": 1
}

The collection now contains the following documents:

{ "_id" : 1, "name" : "Central Perk Cafe", "Borough" : "Manhattan", "violations" : 3 },
{ "_id" : 2, "name" : "Rock A Feller Bar and Grill", "Borough" : "Queens", "violations" : 2 },
{ "_id" : 3, "name" : "Empire State Pub", "Borough" : "Brooklyn", "violations" : 4 },
{ "_id" : 4, "name" : "Pizza Rat's Pizzaria", "Borough" : "Manhattan", "violations" : 7 }

The name field was filled in using the filter criteria, while the update operators were used to create the rest of the document.

The following operation updates the first document with violations that are greater than 10:

try {
   db.restaurant.updateOne(
      { "violations" : { $gt: 10} },
      { $set: { "Closed" : true } },
      { upsert: true }
   );
} catch (e) {
   print(e);
}

The operation returns:

{
   "acknowledged" : true,
   "matchedCount" : 0,
   "modifiedCount" : 0,
   "upsertedId" : ObjectId("56310c3c0c5cbb6031cafaea")
}

The collection now contains the following documents:

{ "_id" : 1, "name" : "Central Perk Cafe", "Borough" : "Manhattan", "violations" : 3 },
{ "_id" : 2, "name" : "Rock A Feller Bar and Grill", "Borough" : "Queens", "violations" : 2 },
{ "_id" : 3, "name" : "Empire State Pub", "Borough" : "Brooklyn", "violations" : 4 },
{ "_id" : 4, "name" : "Pizza Rat's Pizzaria", "Borough" : "Manhattan", "grade" : 7 }
{ "_id" : ObjectId("56310c3c0c5cbb6031cafaea"), "Closed" : true }

Since no documents matched the filter, and upsert was true, updateOne() inserted the document with a generated _id and the update criteria only.

Update with Write Concern

Given a three member replica set, the following operation specifies a w of majority, wtimeout of 100:

try {
   db.restaurant.updateOne(
       { "name" : "Pizza Rat's Pizzaria" },
       { $inc: { "violations" : 3}, $set: { "Closed" : true } },
       { w: "majority", wtimeout: 100 }
   );
} catch (e) {
   print(e);
}

If the primary and at least one secondary acknowledge each write operation within 100 milliseconds, it returns:

{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }

If the acknowledgment takes longer than the wtimeout limit, the following exception is thrown:

WriteConcernError({
   "code" : 64,
   "errmsg" : "waiting for replication timed out",
   "errInfo" : {
     "wtimeout" : true,
     "writeConcern" : {
       "w" : "majority",
       "wtimeout" : 100,
       "provenance" : "getLastErrorDefaults"
     }
   }
})

The following table explains the possible values of errInfo.writeConcern.provenance:

Provenance	Description
`clientSupplied`	The write concern was specified in the application.
`customDefault`	The write concern originated from a custom defined default value. See `setDefaultRWConcern`.
`getLastErrorDefaults`	The write concern originated from the replica set's `settings.getLastErrorDefaults` field.
`implicitDefault`	The write concern originated from the server in absence of all other write concern specifications.

Specify Collation

Collation allows users to specify language-specific rules for string comparison, such as rules for lettercase and accent marks.

A collection myColl has the following documents:

{ _id: 1, category: "café", status: "A" }
{ _id: 2, category: "cafe", status: "a" }
{ _id: 3, category: "cafE", status: "a" }

The following operation includes the collation option:

db.myColl.updateOne(
   { category: "cafe" },
   { $set: { status: "Updated" } },
   { collation: { locale: "fr", strength: 1 } }
);

Specify `arrayFilters` for an Array Update Operations

When updating an array field, you can specify arrayFilters that determine which array elements to update.

Update Elements Match `arrayFilters` Criteria

Create a collection students with the following documents:

db.students.insertMany( [
   { "_id" : 1, "grades" : [ 95, 92, 90 ] },
   { "_id" : 2, "grades" : [ 98, 100, 102 ] },
   { "_id" : 3, "grades" : [ 95, 110, 100 ] }
] )

To modify all elements that are greater than or equal to 100 in the grades array, use the filtered positional operator $[<identifier>] with the arrayFilters option in the db.collection.updateOne() method:

db.students.updateOne(
   { grades: { $gte: 100 } },
   { $set: { "grades.$[element]" : 100 } },
   { arrayFilters: [ { "element": { $gte: 100 } } ] }
)

The operation updates the grades field of a single document, and after the operation, the collection has the following documents:

{ "_id" : 1, "grades" : [ 95, 92, 90 ] }
{ "_id" : 2, "grades" : [ 98, 100, 100 ] }
{ "_id" : 3, "grades" : [ 95, 110, 100 ] }

Update Specific Elements of an Array of Documents

Create a collection students2 with the following documents:

db.students2.insertMany( [
   {
      "_id" : 1,
      "grades" : [
         { "grade" : 80, "mean" : 75, "std" : 6 },
         { "grade" : 85, "mean" : 90, "std" : 4 },
         { "grade" : 85, "mean" : 85, "std" : 6 }
      ]
   },
   {
      "_id" : 2,
      "grades" : [
         { "grade" : 90, "mean" : 75, "std" : 6 },
         { "grade" : 87, "mean" : 90, "std" : 3 },
         { "grade" : 85, "mean" : 85, "std" : 4 }
      ]
   }
] )

To modify the value of the mean field for all elements in the grades array where the grade is greater than or equal to 85, use the filtered positional operator $[<identifier>] with the arrayFilters in the db.collection.updateOne() method:

db.students2.updateOne(
   { },
   { $set: { "grades.$[elem].mean" : 100 } },
   { arrayFilters: [ { "elem.grade": { $gte: 85 } } ] }
)

The operation updates the array of a single document, and after the operation, the collection has the following documents:

{
   "_id" : 1,
   "grades" : [
      { "grade" : 80, "mean" : 75, "std" : 6 },
      { "grade" : 85, "mean" : 100, "std" : 4 },
      { "grade" : 85, "mean" : 100, "std" : 6 }
    ]
}
{
   "_id" : 2,
   "grades" : [
      { "grade" : 90, "mean" : 75, "std" : 6 },
      { "grade" : 87, "mean" : 90, "std" : 3 },
      { "grade" : 85, "mean" : 85, "std" : 4 }
   ]
}

Specify `hint` for Update Operations

Create a sample students collection with the following documents:

db.students.insertMany( [
   { "_id" : 1, "student" : "Richard", "grade" : "F", "points" :  0,  "comments1" : null, "comments2" : null },
   { "_id" : 2, "student" : "Jane", "grade" : "A", "points" : 60,  "comments1" : "well behaved", "comments2" : "fantastic student" },
   { "_id" : 3, "student" : "Ronan", "grade" : "F", "points" :  0,  "comments1" : null, "comments2" : null },
   { "_id" : 4, "student" : "Noah", "grade" : "D", "points" : 20,  "comments1" : "needs improvement", "comments2" : null },
   { "_id" : 5, "student" : "Adam", "grade" : "F", "points" :  0,  "comments1" : null, "comments2" : null },
   { "_id" : 6, "student" : "Henry", "grade" : "A", "points" : 86,  "comments1" : "fantastic student", "comments2" : "well behaved" }
] )

Create the following indexes on the collection:

db.students.createIndex( { grade: 1 } )
db.students.createIndex( { points: 1 } )

The following update operation explicitly hints to use the index { grade: 1 }:

Note

If you specify an index that does not exist, the operation errors.

db.students.updateOne(
   { "points": { $lte: 20 }, "grade": "F" },
   { $set: { "comments1": "failed class" } },
   { hint: { grade: 1 } }
)

The update command returns the following:

{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }

Note

Even though 3 documents match the criteria of the update, updateOne only modifies the first document it finds. Therefore, even though the students Richard, Ronan, and Adam all meet the criteria, only Richard will be updated.

To see the index used, run explain on the operation:

db.students.explain().update(
   { "points": { $lte: 20 }, "grade": "F" },
   { $set: { "comments1": "failed class" } },
   { multi: true, hint: { grade: 1 } }
)

User Roles and Document Updates

Starting in MongoDB 7.0, you can use the new USER_ROLES system variable to return user roles.

The example in this section shows updates to fields in a collection containing medical information. The example reads the current user roles from the USER_ROLES system variable and only performs the updates if the user has a specific role.

To use a system variable, add $$ to the start of the variable name. Specify the USER_ROLES system variable as $$USER_ROLES.

The example creates these users:

James with a Billing role.
Michelle with a Provider role.

Perform the following steps to create the roles, users, and collection:

Create the roles

Create roles named Billing and Provider with the required privileges and resources.

Run:

db.createRole( { role: "Billing", privileges: [ { resource: { db: "test",
   collection: "medicalView" }, actions: [ "find" ] } ], roles: [ ] } )
db.createRole( { role: "Provider", privileges: [ { resource: { db: "test",
   collection: "medicalView" }, actions: [ "find" ] } ], roles: [ ] } )

Create the users

Create users named James and Michelle with the required roles.

db.createUser( {
   user: "James",
   pwd: "js008",
   roles: [
      { role: "Billing", db: "test" }
   ]
} )
db.createUser( {
   user: "Michelle",
   pwd: "me009",
   roles: [
      { role: "Provider", db: "test" }
   ]
} )

Create the collection

Run:

db.medical.insertMany( [
   {
      _id: 0,
      patientName: "Jack Jones",
      diagnosisCode: "CAS 17",
      creditCard: "1234-5678-9012-3456"
   },
   {
      _id: 1,
      patientName: "Mary Smith",
      diagnosisCode: "ACH 01",
      creditCard: "6541-7534-9637-3456"
   }
] )

Log in as `Michelle`

Run:

db.auth( "Michelle", "me009" )

Perform update

Run:

// Attempt to update one document
db.medical.updateOne( {
   // User must have the Provider role to perform the update
   $expr: { $ne: [
      { $setIntersection: [ [ "Provider" ], "$$USER_ROLES.role" ] }, []
   ] } },
   // Update diagnosisCode
   { $set: { diagnosisCode: "ACH 01"} }
)

The previous example uses $setIntersection to return documents where the intersection between the "Provider" string and the user roles from $$USER_ROLES.role is not empty. Michelle has the Provider role, so the update is performed.

Next, log in as as James, who does not have the Provider role, and attempt to perform the same update:

Log in as `James`

Run:

db.auth( "James", "js008" )

Attempt to perform update

Run:

// Attempt to update one document
db.medical.updateOne( {
   // User must have the Provider role to perform the update
   $expr: { $ne: [
      { $setIntersection: [ [ "Provider" ], "$$USER_ROLES.role" ] }, []
   ] } },
   // Update diagnosisCode
   { $set: { diagnosisCode: "ACH 01"} }
)

The previous example does not update any documents.

Definition

Compatibility

Syntax

Parameters

Note

Note

Returns

Access Control

Behavior

Updates a Single Document

Update with an Update Operator Expressions Document

Update with an Aggregation Pipeline

Note

Upsert

Capped Collection

Sharded Collections

upsert on a Sharded Collection

Shard Key Modification

Warning

Missing Shard Key

Tip

Explainability

Transactions

Important

Upsert within Transactions

Tip

See also:

Write Concerns and Transactions

Oplog Entries

Examples

Update using Update Operator Expressions

Update with Aggregation Pipeline

Example 1

Note

Example 2

Note

Tip

See also:

Update with Upsert

Update with Write Concern

Specify Collation

Specify arrayFilters for an Array Update Operations

Update Elements Match arrayFilters Criteria

Update Specific Elements of an Array of Documents

Specify hint for Update Operations

Note

Note

User Roles and Document Updates

Create the roles

Create the users

Create the collection

Log in as Michelle

Perform update

Log in as James

Attempt to perform update

Tip

See also:

`upsert` on a Sharded Collection

Specify `arrayFilters` for an Array Update Operations

Update Elements Match `arrayFilters` Criteria

Specify `hint` for Update Operations

Log in as `Michelle`

Log in as `James`