On this page

• Definition
• Behavior
• Examples

Definition

db.collection. replaceOne ( filter, replacement, options )

New in version 3.2.

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

The replaceOne() method has the following form:

copy

db.collection.replaceOne(
   <filter>,
   <replacement>,
   {
     upsert: <boolean>,
     writeConcern: <document>,
     collation: <document>
   }
)

The replaceOne() 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 replace the first document returned in the collection.
replacement	document	The replacement document. Cannot contain update operators.
upsert	boolean	Optional. When true, replaceOne() either: Inserts the document from the replacement parameter if no document matches the filter. Replaces the document that matches the filter with the replacement document. MongoDB will add the _id field to the replacement document if it is not specified in either the filter or replacement documents. If _id is present in both, the values must be equal. To avoid multiple upserts, ensure that the query 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.

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

replaceOne() replaces the first matching document in the collection that matches the filter, using the replacement document.

If upsert: true and no documents match the filter, replaceOne() creates a new document based on the replacement document. See Replace 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.replaceOne(
      { "name" : "Central Perk Cafe" },
      { "name" : "Central Pork Cafe", "Borough" : "Manhattan" }
   );
} 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.replaceOne(
      { "name" : "Pizza Rat's Pizzaria" },
      { "_id": 4, "name" : "Pizza Rat's Pizzaria", "Borough" : "Manhattan", "violations" : 8 },
      { upsert: true }
   );
} catch (e){
   print(e);
}

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

{ "_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 },
{ "_id" : 4, "name" : "Pizza Rat's Pizzaria", "Borough" : "Manhattan", "violations" : 8 }

try {
   db.restaurant.replaceOne(
       { "name" : "Pizza Rat's Pizzaria" },
       { "name" : "Pizza Rat's Pub", "Borough" : "Manhattan", "violations" : 3 },
       { w: "majority", wtimeout: 100 }
   );
} catch (e) {
   print(e);
}

WriteConcernError({
   "code" : 64,
   "errInfo" : {
      "wtimeout" : true
   },
   "errmsg" : "waiting for replication timed out"
})

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