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Definition

db.collection. updateOne ( filter, update, options )

New in version 3.2.

Updates a single document within the collection based on the filter.

The updateOne() method has the following form:

Changed in version 3.6.

copy

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

The 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	The modifications to apply. Use Update Operators such as $set, $unset, or $rename. Using the update() pattern of field: value for the update parameter throws an error.
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 fields are uniquely indexed. Defaults to false.
writeConcern	document	Optional. A document expressing the write concern. Omit to use the default 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: copy 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. New in version 3.4.
arrayFilters	array	Optional. An array of filter documents that determines 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: copy [ { "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: copy [ { $or: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] } ] [ { $and: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] } ] [ { "x.a": { $gt: 85 }, "x.b": { $gt: 80 } } ] For examples, see Specify arrayFilters for an Array Update Operations. New in version 3.6.

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

Behavior

updateOne() updates the first matching document in the collection that matches the filter, using the update instructions to apply modifications.

If upsert: true and no documents match the filter, updateOne() creates a new document based on the filter criteria and update modifications. See Update with Upsert.

Examples

{ "_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 }

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

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

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

{ "_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" }

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

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