APPLIES TO:
MongoDB
Azure Cosmos DB is Azure's multiple-regionally distributed multi-model database service. You can communicate with the Azure Cosmos DB for MongoDB using any of the open-source MongoDB client drivers. The Azure Cosmos DB for MongoDB enables the use of existing client drivers by adhering to the MongoDB wire protocol.
By using the Azure Cosmos DB for MongoDB, you can enjoy the benefits of the MongoDB you're used to, with all of the enterprise capabilities that Azure Cosmos DB provides: multiple-region distribution, automatic sharding, availability and latency guarantees, encryption at rest, backups, and much more.
Note
Version 3.6 of the Azure Cosmos DB for MongoDB has no current plans for end-of-life (EOL). The minimum notice for a future EOL is three years.
Protocol Support
The Azure Cosmos DB for MongoDB is compatible with MongoDB server version 3.6 by default for new accounts. The supported operators and any limitations or exceptions are listed below. Any client driver that understands these protocols should be able to connect to Azure Cosmos DB for MongoDB. When you create Azure Cosmos DB API for MongoDB accounts, the 3.6 version of account has the endpoint in the format *.mongo.cosmos.azure.cn
whereas the 3.2 version of account has the endpoint in the format *.documents.azure.cn
.
Query language support
Azure Cosmos DB for MongoDB provides comprehensive support for MongoDB query language constructs. The following sections show the detailed list of server operations, operators, stages, commands, and options currently supported by Azure Cosmos DB.
Note
This article only lists the supported server commands and excludes client-side wrapper functions. Client-side wrapper functions such as deleteMany()
and updateMany()
internally utilize the delete()
and update()
server commands. Functions utilizing supported server commands are compatible with Azure Cosmos DB for MongoDB.
Database commands
Azure Cosmos DB for MongoDB supports the following database commands:
Query and write operation commands
Command |
Supported |
change streams |
Yes |
delete |
Yes |
eval |
No |
find |
Yes |
findAndModify |
Yes |
getLastError |
Yes |
getMore |
Yes |
getPrevError |
No |
insert |
Yes |
parallelCollectionScan |
No |
resetError |
No |
update |
Yes |
Authentication commands
Command |
Supported |
authenticate |
Yes |
getnonce |
Yes |
logout |
Yes |
Administration commands
Command |
Supported |
cloneCollectionAsCapped |
No |
collMod |
No |
connectionStatus |
No |
convertToCapped |
No |
copydb |
No |
create |
Yes |
createIndexes |
Yes |
currentOp |
Yes |
drop |
Yes |
dropDatabase |
Yes |
dropIndexes |
Yes |
filemd5 |
Yes |
killCursors |
Yes |
killOp |
No |
listCollections |
Yes |
listDatabases |
Yes |
listIndexes |
Yes |
reIndex |
Yes |
renameCollection |
No |
Diagnostics commands
Command |
Supported |
buildInfo |
Yes |
collStats |
Yes |
connPoolStats |
No |
connectionStatus |
No |
dataSize |
No |
dbHash |
No |
dbStats |
Yes |
explain |
Yes |
features |
No |
hello |
Yes |
hostInfo |
Yes |
listDatabases |
Yes |
listCommands |
No |
profiler |
No |
serverStatus |
No |
top |
No |
whatsmyuri |
Yes |
Aggregation pipeline
Aggregation commands
Command |
Supported |
aggregate |
Yes |
count |
Yes |
distinct |
Yes |
mapReduce |
No |
Aggregation stages
Command |
Supported |
addFields |
Yes |
bucket |
No |
bucketAuto |
No |
changeStream |
Yes |
collStats |
No |
count |
Yes |
currentOp |
No |
facet |
Yes |
geoNear |
Yes |
graphLookup |
Yes |
group |
Yes |
indexStats |
No |
limit |
Yes |
listLocalSessions |
No |
listSessions |
No |
lookup |
Partial |
match |
Yes |
out |
Yes |
project |
Yes |
redact |
Yes |
replaceRoot |
Yes |
replaceWith |
No |
sample |
Yes |
skip |
Yes |
sort |
Yes |
sortByCount |
Yes |
unwind |
Yes |
Note
$lookup
does not yet support the uncorrelated subqueries feature introduced in server version 3.6. You will receive an error with a message containing let is not supported
if you attempt to use the $lookup
operator with let
and pipeline
fields.
Boolean expressions
Command |
Supported |
and |
Yes |
not |
Yes |
or |
Yes |
Set expressions
Command |
Supported |
setEquals |
Yes |
setIntersection |
Yes |
setUnion |
Yes |
setDifference |
Yes |
setIsSubset |
Yes |
anyElementTrue |
Yes |
allElementsTrue |
Yes |
Comparison expressions
Note
The API for MongoDB does not support comparison expressions with an array literal in the query.
Command |
Supported |
cmp |
Yes |
eq |
Yes |
gt |
Yes |
gte |
Yes |
lt |
Yes |
lte |
Yes |
ne |
Yes |
in |
Yes |
nin |
Yes |
Arithmetic expressions
Command |
Supported |
abs |
Yes |
add |
Yes |
ceil |
Yes |
divide |
Yes |
exp |
Yes |
floor |
Yes |
ln |
Yes |
log |
Yes |
log10 |
Yes |
mod |
Yes |
multiply |
Yes |
pow |
Yes |
sqrt |
Yes |
subtract |
Yes |
trunc |
Yes |
String expressions
Command |
Supported |
concat |
Yes |
indexOfBytes |
Yes |
indexOfCP |
Yes |
split |
Yes |
strLenBytes |
Yes |
strLenCP |
Yes |
strcasecmp |
Yes |
substr |
Yes |
substrBytes |
Yes |
substrCP |
Yes |
toLower |
Yes |
toUpper |
Yes |
Text search operator
Command |
Supported |
meta |
No |
Array expressions
Command |
Supported |
arrayElemAt |
Yes |
arrayToObject |
Yes |
concatArrays |
Yes |
filter |
Yes |
indexOfArray |
Yes |
isArray |
Yes |
objectToArray |
Yes |
range |
Yes |
reverseArray |
Yes |
reduce |
Yes |
size |
Yes |
slice |
Yes |
zip |
Yes |
in |
Yes |
Variable operators
Command |
Supported |
map |
Yes |
let |
Yes |
System variables
Command |
Supported |
$$CURRENT |
Yes |
$$DESCEND |
Yes |
$$KEEP |
Yes |
$$PRUNE |
Yes |
$$REMOVE |
Yes |
$$ROOT |
Yes |
Literal operator
Command |
Supported |
literal |
Yes |
Date expressions
Command |
Supported |
dayOfYear |
Yes |
dayOfMonth |
Yes |
dayOfWeek |
Yes |
year |
Yes |
month |
Yes |
week |
Yes |
hour |
Yes |
minute |
Yes |
second |
Yes |
millisecond |
Yes |
dateToString |
Yes |
isoDayOfWeek |
Yes |
isoWeek |
Yes |
dateFromParts |
Yes |
dateToParts |
Yes |
dateFromString |
Yes |
isoWeekYear |
Yes |
Conditional expressions
Command |
Supported |
cond |
Yes |
ifNull |
Yes |
switch |
Yes |
Data type operator
Command |
Supported |
type |
Yes |
Accumulator expressions
Command |
Supported |
sum |
Yes |
avg |
Yes |
first |
Yes |
last |
Yes |
max |
Yes |
min |
Yes |
push |
Yes |
addToSet |
Yes |
stdDevPop |
Yes |
stdDevSamp |
Yes |
Merge operator
Command |
Supported |
mergeObjects |
Yes |
Data types
Command |
Supported |
Double |
Yes |
String |
Yes |
Object |
Yes |
Array |
Yes |
Binary Data |
Yes |
ObjectId |
Yes |
Boolean |
Yes |
Date |
Yes |
Null |
Yes |
32-bit Integer (int) |
Yes |
Timestamp |
Yes |
64-bit Integer (long) |
Yes |
MinKey |
Yes |
MaxKey |
Yes |
Decimal128 |
Yes |
Regular Expression |
Yes |
JavaScript |
Yes |
JavaScript (with scope) |
Yes |
Undefined |
Yes |
Indexes and index properties
Indexes
Command |
Supported |
Single Field Index |
Yes |
Compound Index |
Yes |
Multikey Index |
Yes |
Text Index |
No |
2dsphere |
Yes |
2d Index |
No |
Hashed Index |
No |
Index properties
Command |
Supported |
TTL |
Yes |
Unique |
Yes |
Partial |
No |
Case Insensitive |
No |
Sparse |
No |
Background |
Yes |
Operators
Logical operators
Command |
Supported |
or |
Yes |
and |
Yes |
not |
Yes |
nor |
Yes |
Element operators
Command |
Supported |
exists |
Yes |
type |
Yes |
Evaluation query operators
Command |
Supported |
expr |
Yes |
jsonSchema |
No |
mod |
Yes |
regex |
Yes |
text |
No (Not supported. Use $regex instead.) |
where |
No |
In the $regex queries, left-anchored expressions allow index search. However, using 'i' modifier (case-insensitivity) and 'm' modifier (multiline) causes the collection scan in all expressions.
When there's a need to include $
or |
, it's best to create two (or more) regex queries. For example, given the following original query: find({x:{$regex: /^abc$/})
, it has to be modified as follows:
find({x:{$regex: /^abc/, x:{$regex:/^abc$/}})
The first part will use the index to restrict the search to those documents beginning with ^abc and the second part will match the exact entries. The bar operator |
acts as an "or" function - the query find({x:{$regex: /^abc |^def/})
matches the documents in which field x
has values that begin with "abc"
or "def"
. To utilize the index, it's recommended to break the query into two different queries joined by the $or operator: find( {$or : [{x: $regex: /^abc/}, {$regex: /^def/}] })
.
Array operators
Command |
Supported |
all |
Yes |
elemMatch |
Yes |
size |
Yes |
Command |
Supported |
comment |
Yes |
Projection operators
Command |
Supported |
elemMatch |
Yes |
meta |
No |
slice |
Yes |
Update operators
Field update operators
Command |
Supported |
inc |
Yes |
mul |
Yes |
rename |
Yes |
setOnInsert |
Yes |
set |
Yes |
unset |
Yes |
min |
Yes |
max |
Yes |
currentDate |
Yes |
Array update operators
Command |
Supported |
$ |
Yes |
$[] |
Yes |
$[\<identifier\>] |
Yes |
addToSet |
Yes |
pop |
Yes |
pullAll |
Yes |
pull |
Yes |
push |
Yes |
pushAll |
Yes |
Update modifiers
Command |
Supported |
each |
Yes |
slice |
Yes |
sort |
Yes |
position |
Yes |
Bitwise update operator
Command |
Supported |
bit |
Yes |
bitsAllSet |
No |
bitsAnySet |
No |
bitsAllClear |
No |
bitsAnyClear |
No |
Geospatial operators
Operator |
Supported |
$geoWithin |
Yes |
$geoIntersects |
Yes |
$near |
Yes |
$nearSphere |
Yes |
$geometry |
Yes |
$minDistance |
Yes |
$maxDistance |
Yes |
$center |
No |
$centerSphere |
No |
$box |
No |
$polygon |
No |
Sort operations
When you use the findOneAndUpdate
operation, sort operations on a single field are supported, but sort operations on multiple fields aren't supported.
Indexing
The API for MongoDB supports various indexes to enable sorting on multiple fields, improve query performance, and enforce uniqueness.
GridFS
Azure Cosmos DB supports GridFS through any GridFS-compatible MongoDB driver.
Replication
Azure Cosmos DB supports automatic, native replication at the lowest layers. This logic is extended out to achieve low-latency, multiple-region replication as well. Azure Cosmos DB doesn't support manual replication commands.
Retryable Writes
Azure Cosmos DB doesn't yet support retryable writes. Client drivers must add retryWrites=false
to their connection string.
Sharding
Azure Cosmos DB supports automatic, server-side sharding. It manages shard creation, placement, and balancing automatically. Azure Cosmos DB doesn't support manual sharding commands, which means you don't have to invoke commands such as addShard, balancerStart, moveChunk etc. You only need to specify the shard key while creating the containers or querying the data.
Sessions
Azure Cosmos DB doesn't yet support server-side sessions commands.
Time-to-live (TTL)
Azure Cosmos DB supports a time-to-live (TTL) based on the timestamp of the document. TTL can be enabled for collections from the Azure portal.
User and role management
Azure Cosmos DB doesn't yet support users and roles. However, it supports Azure role-based access control (Azure RBAC) and read-write and read-only passwords or keys that can be obtained through the connection string pane in the Azure portal.
Write Concern
Some applications rely on a Write Concern, which specifies the number of responses required during a write operation. Due to how Azure Cosmos DB handles replication, all writes are automatically majority quorum by default when using strong consistency. Any write concern specified by the client code is ignored. To learn more, see Using consistency levels to maximize availability and performance article.
Next steps