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- db.collection.insertMany()
db.collection.insertMany()¶
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Definition¶
-
db.collection.
insertMany
()¶ New in version 3.2.
Inserts multiple documents into a collection.
The
insertMany()
method has the following syntax:db.collection.insertMany( [ <document 1> , <document 2>, ... ], { writeConcern: <document>, ordered: <boolean> } )
Parameter Type Description document
document An array of documents to insert into the collection. writeConcern
document Optional. A document expressing the write concern. Omit to use the default write concern. ordered
boolean Optional. A boolean specifying whether the mongod
instance should perform an ordered or unordered insert. Defaults totrue
.Returns: A document containing: - A boolean
acknowledged
astrue
if the operation ran with write concern orfalse
if write concern was disabled - An array of
_id
for each successfully inserted documents
- A boolean
Behaviors¶
Given an array of documents, insertMany()
inserts each document in the array into the collection.
Execution of Operations¶
By default documents are inserted in order.
If ordered
is set to false, documents are inserted in an unordered
format and may be reordered by mongod
to increase performance.
Applications should not depend on ordering of inserts if using an unordered
insertMany()
.
Each group of operations can have at most
1000 operations
.
If a group exceeds this limit
,
MongoDB will divide the group into
smaller groups of 1000 or less. For example, if the queue consists of 2000
operations, MongoDB creates 2 groups, each with 1000 operations.
The sizes and grouping mechanics are internal performance details and are subject to change in future versions.
Executing an ordered
list of operations on a
sharded collection will generally be slower than executing an
unordered
list
since with an ordered list, each operation must wait for the previous
operation to finish.
Collection Creation¶
If the collection does not exist, then insertMany()
creates the collection on successful write.
_id
Field¶
If the document does not specify an _id field, then mongod
adds the _id
field and assign a unique
ObjectId
for the document. Most
drivers create an ObjectId and insert the _id
field, but the
mongod
will create and populate the _id
if the driver or
application does not.
If the document contains an _id
field, the _id
value must be
unique within the collection to avoid duplicate key error.
Error Handling¶
Inserts throw a BulkWriteError
exception.
Excluding Write Concern errors, ordered operations stop after an error, while unordered operations continue to process any remaining write operations in the queue.
Write concern errors are displayed in the writeConcernErrors
field, while
all other errors are displayed in the writeErrors
field. If an error is
encountered, the number of successful write operations are displayed instead
of a list of inserted _ids. Ordered operations display the single error
encountered while unordered operations display each error in an array.
Examples¶
The following examples insert documents into the products
collection.
Insert Several Document without Specifying an _id
Field¶
The following example uses db.collection.insertMany()
to insert
documents that do not contain the _id
field:
try {
db.products.insertMany( [
{ item: "card", qty: 15 },
{ item: "envelope", qty: 20 },
{ item: "stamps" , qty: 30 }
] );
} catch (e) {
print (e);
}
The operation returns the following document:
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("562a94d381cb9f1cd6eb0e1a"),
ObjectId("562a94d381cb9f1cd6eb0e1b"),
ObjectId("562a94d381cb9f1cd6eb0e1c")
]
}
Because the documents did not include _id
,
mongod
creates and adds the _id
field for each document and
assigns it a unique ObjectId
value.
The ObjectId
values are specific to the machine and time when the
operation is run. As such, your values may differ from those in the
example.
Insert Several Document Specifying an _id
Field¶
The following example/operation uses insertMany()
to
insert documents that include the _id
field. The value of _id
must be
unique within the collection to avoid a duplicate key error.
try {
db.products.insertMany( [
{ _id: 10, item: "large box", qty: 20 },
{ _id: 11, item: "small box", qty: 55 },
{ _id: 12, item: "medium box", qty: 30 }
] );
} catch (e) {
print (e);
}
The operation returns the following document:
{ "acknowledged" : true, "insertedIds" : [ 10, 11, 12 ] }
Inserting a duplicate value for any key that is part of a unique
index, such as _id
, throws an exception. The following attempts to insert
a document with a _id
value that already exists:
try {
db.products.insertMany( [
{ _id: 13, item: "envelopes", qty: 60 },
{ _id: 13, item: "stamps", qty: 110 },
{ _id: 14, item: "packing tape", qty: 38 }
] );
} catch (e) {
print (e);
}
Since _id: 13
already exists, the following exception is thrown:
BulkWriteError({
"writeErrors" : [
{
"index" : 0,
"code" : 11000,
"errmsg" : "E11000 duplicate key error collection: inventory.products index: _id_ dup key: { : 13.0 }",
"op" : {
"_id" : 13,
"item" : "stamps",
"qty" : 110
}
}
],
"writeConcernErrors" : [ ],
"nInserted" : 1,
"nUpserted" : 0,
"nMatched" : 0,
"nModified" : 0,
"nRemoved" : 0,
"upserted" : [ ]
})
Note that one document was inserted: The first document of _id: 13
will
insert successfully, but the second insert will fail. This will also stop
additional documents left in the queue from being inserted.
With ordered
to false
, the insert operation would continue with any
remaining documents.
Unordered Inserts¶
The following attempts to insert multiple documents with _id
field and
ordered: false
. The array of documents contains two documents with
duplicate _id
fields.
try {
db.products.insertMany( [
{ _id: 10, item: "large box", qty: 20 },
{ _id: 11, item: "small box", qty: 55 },
{ _id: 11, item: "medium box", qty: 30 },
{ _id: 12, item: "envelope", qty: 100},
{ _id: 13, item: "stamps", qty: 125 },
{ _id: 13, item: "tape", qty: 20},
{ _id: 14, item: "bubble wrap", qty: 30}
], { ordered: false } );
} catch (e) {
print (e);
}
The operation throws the following exception:
BulkWriteError({
"writeErrors" : [
{
"index" : 2,
"code" : 11000,
"errmsg" : "E11000 duplicate key error collection: inventory.products index: _id_ dup key: { : 11.0 }",
"op" : {
"_id" : 11,
"item" : "medium box",
"qty" : 30
}
},
{
"index" : 5,
"code" : 11000,
"errmsg" : "E11000 duplicate key error collection: inventory.products index: _id_ dup key: { : 13.0 }",
"op" : {
"_id" : 13,
"item" : "tape",
"qty" : 20
}
}
],
"writeConcernErrors" : [ ],
"nInserted" : 5,
"nUpserted" : 0,
"nMatched" : 0,
"nModified" : 0,
"nRemoved" : 0,
"upserted" : [ ]
})
While the document with item: "medium box"
and item: "tape"
failed to insert due to duplicate _id
values,
nInserted
shows that the remaining 5 documents were inserted.
Using Write Concern¶
Given a three member replica set, the following operation specifies a
w
of majority
and wtimeout
of 100
:
try {
db.products.insertMany(
[
{ _id: 10, item: "large box", qty: 20 },
{ _id: 11, item: "small box", qty: 55 },
{ _id: 12, item: "medium box", qty: 30 }
],
{ w: "majority", wtimeout: 100 }
);
} catch (e) {
print (e);
}
If the primary and at least one secondary acknowledge each write operation within 100 milliseconds, it returns:
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("562a94d381cb9f1cd6eb0e1a"),
ObjectId("562a94d381cb9f1cd6eb0e1b"),
ObjectId("562a94d381cb9f1cd6eb0e1c")
]
}
If the total time required for all required nodes in the replica set to
acknowledge the write operation is greater than wtimeout
,
the following writeConcernError
is displayed when the wtimeout
period
has passed.
This operation returns:
WriteConcernError({
"code" : 64,
"errInfo" : {
"wtimeout" : true
},
"errmsg" : "waiting for replication timed out"
})