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db.collection.replaceOne()¶
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Definition¶
-
db.collection.replaceOne(filter, replacement, options)¶ mongoShell MethodThis page documents the
mongoshell method, and does not refer to the MongoDB Node.js driver (or any other driver) method. For corresponding MongoDB driver API, refer to your specific MongoDB driver documentation instead.Replaces a single document within the collection based on the filter.
The
replaceOne()method has the following form: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.replacementdocument The replacement document.
Cannot contain update operators.
upsertboolean Optional. When
true,replaceOne()either:- Inserts the document from the
replacementparameter if no document matches thefilter. - Replaces the document that matches the
filterwith thereplacementdocument.
MongoDB will add the
_idfield to the replacement document if it is not specified in either thefilterorreplacementdocuments. If_idis present in both, the values must be equal.To avoid multiple upserts, ensure that the
queryfields are uniquely indexed.Defaults to
false.writeConcerndocument 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.
collationdocument 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:
When specifying collation, the
localefield 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.
hint document Optional. A document or string that specifies the index to use to support the filter.
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 replaceOne.
New in version 4.2.1.
Returns: A document containing: - A boolean
acknowledgedastrueif the operation ran with write concern orfalseif write concern was disabled matchedCountcontaining the number of matched documentsmodifiedCountcontaining the number of modified documentsupsertedIdcontaining the_idfor the upserted document
- Inserts the document from the
Behavior¶
replaceOne() replaces the first matching document in
the collection that matches the filter, using the replacement
document.
upsert¶
If upsert: true and no documents match the filter,
db.collection.replaceOne() creates a new document based on
the replacement document.
If you specify upsert: true on a sharded collection, you must
include the full shard key in the filter. For additional
db.collection.replaceOne() behavior on a sharded collection,
see Sharded Collections.
See Replace with Upsert.
Capped Collections¶
If a replacement operation changes the document size, the operation will fail.
Sharded Collections¶
Starting in MongoDB 4.2, db.collection.replaceOne() attempts
to target a single shard, first by using the query filter. If the operation
cannot target a single shard by the query filter, it then attempts to target
by the replacement document.
In earlier versions, the operation attempts to target using the replacement document.
If replacing a document in a sharded collection, the replacement document must include the shard key. Additional requirements apply for upsert on a Sharded Collection and Shard Key Modification.
upsert on a Sharded Collection¶
Starting in MongoDB 4.2, for a db.collection.replaceOne()
operation that includes upsert: true and is on a sharded
collection, you must include the full shard key in the filter.
Shard Key Modification¶
Starting in MongoDB 4.2, you can update a document’s shard key value
unless the shard key field is the immutable _id field. For details
on updating the shard key, see Change a Document’s Shard Key Value.
Before MongoDB 4.2, a document’s shard key field value is immutable.
To use db.collection.replaceOne() to update the shard key:
- You must run on a
mongoseither in a transaction or as a retryable write. Do not issue the operation directly on the shard. - You must include an equality condition on the full shard
key in the query filter. For example, if a collection
messagesuses{ country : 1, userid : 1 }as the shard key, to update the shard key for a document, you must includecountry: <value>, userid: <value>in the query filter. You can include additional fields in the query as appropriate.
Transactions¶
db.collection.replaceOne() can be used inside multi-document transactions.
If the operation results in an upsert, the collection must already exist.
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.
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.
Examples¶
Replace¶
The restaurant collection contains the following documents:
The following operation replaces a single document where
name: "Central Perk Cafe":
The operation returns:
If no matches were found, the operation instead returns:
Setting upsert: true would insert the document if no match was found. See
Replace with Upsert
Replace with Upsert¶
The restaurant collection contains the following documents:
The following operation attempts to replace the document with
name : "Pizza Rat's Pizzaria", with upsert : true:
Since upsert : true the document is inserted based on the
replacement document. The operation returns:
The collection now contains the following documents:
Replace with Write Concern¶
Given a three member replica set, the following operation specifies a
w of majority and wtimeout of 100:
If the acknowledgement takes longer than the wtimeout limit, the following
exception is thrown:
Specify Collation¶
New in version 3.4.
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:
The following operation includes the collation option:
Specify hint for replaceOne¶
New in version 4.2.1.
Create a sample members collection with the following documents:
Create the following indexes on the collection:
The following update operation explicitly hints to use the index {
status: 1 }:
Note
If you specify an index that does not exist, the operation errors.
The operation returns the following:
To view the indexes used, you can use the $indexStats pipeline: