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- db.collection.replaceOne()
db.collection.replaceOne()¶
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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: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.
writeConcern
document Optional. A document expressing the write concern. Omit to use the default write concern. upsert
boolean Optional. When
true
,replaceOne()
either:- Inserts the document from the
replacement
parameter if no document matches thefilter
. - Replaces the document that matches the
filter
with thereplacement
document.
MongoDB will add the
_id
field to the replacement document if it is not specified in either thefilter
orreplacement
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
.Returns: A document containing: - A boolean
acknowledged
astrue
if the operation ran with write concern orfalse
if write concern was disabled matchedCount
containing the number of matched documentsmodifiedCount
containing the number of modified documentsupsertedId
containing the_id
for 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.
If upsert: true
and no documents match the filter
,
replaceOne()
creates a new
document based on the replacement
document. See
Replace with Upsert.
Capped Collections¶
If a replacement operation changes the document size, the operation will fail.
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: