db.collection.findOneAndDelete()
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Definition
db.collection.findOneAndDelete( filter, options )
New in version 3.2.
Important
mongosh Method
This page documents a
mongosh
method. This is not the documentation for database commands or language-specific drivers, such as Node.js.For the database command, see the
delete
command.For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.
Deletes a single document based on the
filter
andsort
criteria, returning the deleted document.The
findOneAndDelete()
method has the following form:db.collection.findOneAndDelete( <filter>, { writeConcern: <document>, projection: <document>, sort: <document>, maxTimeMS: <number>, collation: <document> } ) The
findOneAndDelete()
method takes the following parameters:ParameterTypeDescriptionfilter
documentThe selection criteria for the deletion. The same query selectors as in the
find()
method are available.Specify an empty document
{ }
to delete the first document returned in the collection.If unspecified, defaults to an empty document.
If the query argument is not a document, the operation errors.
writeConcern
documentOptional. A document expressing the write concern. Omit to use the default write concern.
{ w: <value>, j: <boolean>, wtimeout: <number> } See Delete A Document Using WriteConcern for usage.
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.
projection
documentOptional. A subset of fields to return.
To return all fields in the returned document, omit this parameter.
If the projection argument is not a document, the operation errors.
sort
documentOptional. Specifies a sorting order for the documents matched by the
filter
.If the sort argument is not a document, the operation errors.
See
cursor.sort()
.maxTimeMS
numberOptional. Specifies a time limit in milliseconds within which the operation must complete within. Throws an error if the limit is exceeded.collation
documentOptional.
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.
New in version 3.4.
Returns: Returns the deleted document.
Behavior
Document Match
findOneAndDelete()
deletes the first matching
document in the collection that matches the filter
.
The sort
parameter can be used to influence which document is deleted.
Projection
Important
Language Consistency
As part of making find()
and
findAndModify()
projection consistent with
aggregation's $project
stage,
The
find()
andfindAndModify()
projection can accept aggregation expressions and syntax.MongoDB enforces additional restrictions with regards to projections. See Projection Restrictions for details.
The projection
parameter takes a document in the following form:
{ field1: <value>, field2: <value> ... }
Projection | Description |
---|---|
<field>: <1 or true> | Specifies the inclusion of a field. If you specify a non-zero
integer for the projection value, the operation treats the
value as true . |
<field>: <0 or false> | Specifies the exclusion of a field. |
"<field>.$": <1 or true> | |
<field>: <array projection> | Uses the array projection operators ( Not available for views. |
<field>: <aggregation expression> | Specifies the value of the projected field. With the use of aggregation expressions and syntax, including the use of literals and aggregation variables, you can project new fields or project existing fields with new values.
|
Embedded Field Specification
For fields in an embedded documents, you can specify the field using either:
dot notation, for example
"field.nestedfield": <value>
nested form, for example
{ field: { nestedfield: <value> } }
_id
Field Projection
The _id
field is included in the returned documents by default unless
you explicitly specify _id: 0
in the projection to suppress the field.
Inclusion or Exclusion
A projection
cannot contain both include and exclude
specifications, with the exception of the _id
field:
In projections that explicitly include fields, the
_id
field is the only field that you can explicitly exclude.In projections that explicitly excludes fields, the
_id
field is the only field that you can explicitly include; however, the_id
field is included by default.
For more information on projection, see also:
Sharded Collections
When using db.collection.findOneAndDelete()
against a sharded
collection, the query
must contain an equality condition on
shard key.
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
Transactions
db.collection.findOneAndDelete()
can be used inside distributed transactions.
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, 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.
Oplog Entries
If a db.collection.findOneAndDelete()
operation successfully deletes
a document, the operation adds an entry on the oplog (operations
log). If the operation fails or does not find a document to delete, the
operation does not add an entry on the oplog.
Examples
Delete A Document
The scores
collection contains documents similar to the following:
db.scores.insertMany( [ { _id: 6305, name : "A. MacDyver", "assignment" : 5, "points" : 24 }, { _id: 6308, name : "B. Batlock", "assignment" : 3, "points" : 22 }, { _id: 6312, name : "M. Tagnum", "assignment" : 5, "points" : 30 }, { _id: 6319, name : "R. Stiles", "assignment" : 2, "points" : 12 }, { _id: 6322, name : "A. MacDyver", "assignment" : 2, "points" : 14 }, { _id: 6234, name : "R. Stiles", "assignment" : 1, "points" : 10 } ] )
The following operation finds the first document where name : M. Tagnum
and deletes it:
db.scores.findOneAndDelete( { "name" : "M. Tagnum" } )
The operation returns the original document that has been deleted:
{ _id: 6312, name: "M. Tagnum", "assignment" : 5, "points" : 30 }
Delete A Document Using WriteConcern
The scores
collection contains documents similar to the following:
db.scores.insertMany( [ { _id: 6305, name : "A. MacDyver", "assignment" : 5, "points" : 24 }, { _id: 6308, name : "B. Batlock", "assignment" : 3, "points" : 22 }, { _id: 6312, name : "M. Tagnum", "assignment" : 5, "points" : 30 }, { _id: 6319, name : "R. Stiles", "assignment" : 2, "points" : 12 }, { _id: 6322, name : "A. MacDyver", "assignment" : 2, "points" : 14 }, { _id: 6234, name : "R. Stiles", "assignment" : 1, "points" : 10 } ] )
The following operation uses a write concern document inside of the
db.collection.findOneAndDelete()
method with options:
w:1
to requests acknowledgment that the write operation has propagated to the standalone mongod or the primary in a replica set.j:true
to tell the number of MongoDB instances specified inw:1
to have the delete written to on-disk journel.wtimeout : 1000
to specify a time limit, in milliseconds, for the write concern.wtimeout
is only applicable forw
values greater than 1.
db.scores.findOneAndDelete( { name: "A. MacDyver" }, { writeConcern: { w : 1, j : true, wtimeout : 1000 } } )
The operation returns the following document:
{ _id: 6305, name: 'A. MacDyver', assignment: 5, points: 24 }
The document is deleted with the writeConcern options specified.
Sort And Delete A Document
The scores
collection contains documents similar to the following:
db.scores.insertMany( [ { _id: 6305, name : "A. MacDyver", "assignment" : 5, "points" : 24 }, { _id: 6308, name : "B. Batlock", "assignment" : 3, "points" : 22 }, { _id: 6312, name : "M. Tagnum", "assignment" : 5, "points" : 30 }, { _id: 6319, name : "R. Stiles", "assignment" : 2, "points" : 12 }, { _id: 6322, name : "A. MacDyver", "assignment" : 2, "points" : 14 }, { _id: 6234, name : "R. Stiles", "assignment" : 1, "points" : 10 } ] )
The following operation first finds all documents where
name : "A. MacDyver"
. It then sorts by points
ascending before
deleting the document with the lowest points value:
db.scores.findOneAndDelete( { "name" : "A. MacDyver" }, { sort : { "points" : 1 } } )
The operation returns the original document that has been deleted:
{ _id: 6322, name: "A. MacDyver", "assignment" : 2, "points" : 14 }
Projecting the Deleted Document
The following operation uses projection to only return the _id
and
assignment
fields in the returned document:
db.scores.findOneAndDelete( { "name" : "A. MacDyver" }, { sort : { "points" : 1 }, projection: { "assignment" : 1 } } )
The operation returns the original document with the
assignment
and _id
fields:
{ _id: 6322, "assignment" : 2 }
Update Document with Time Limit
The following operation sets a 5ms time limit to complete the deletion:
try { db.scores.findOneAndDelete( { "name" : "A. MacDyver" }, { sort : { "points" : 1 }, maxTimeMS : 5 } ) } catch(e){ print(e) }
If the operation exceeds the time limit, it returns:
MongoServerError: operation exceeded time limit: { "ok": 0, "code" : 50, "codeName" : "MaxTimeMSExpired" }
Note
This error message has been shortened for brevity.
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:
db.myColl.insertMany( [ { _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.findOneAndDelete( { category: "cafe", status: "a" }, { collation: { locale: "fr", strength: 1 } } );
The operation returns the following document:
{ "_id" : 1, "category" : "café", "status" : "A" }