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Cosmos DB

A globally distributed multi-model database service on Microsoft Azure with property graph support through the Apache Gremlin API. Offers multi-region replication and multiple consistency models.

Overall rank
#16
First released
August 2014
License
Proprietary
Built with
C++

Details

Vendor
Microsoft
Type
Multiple
Category
Enterprise
License
Proprietary
Language
C++
Query Languages
GremlinSQL
Protocols
HTTP/RESTGremlin (WebSocket)Native binary

Feature scores

Community & Business

Active development
Updated within last 3 months
Commercial support
Paid support available
Live community
50%
25-50% of issues addressed
Open Source
0%
Closed source
Pricing
Pricing publicly available
Trendiness
Growing or stable trend

Deployment

Containerization
50%
No description available
Work as dedicated instance
Can run as standalone server
Work as embedded
0%
Standalone only
Testing in-memory version
In-memory mode available

Platform

Operating on Linux
0%
Not supported
Operating on Windows
Windows officially supported
SaaS offering
Cloud service available

Operations

Automatic updates
Automatic updates supported
Client side caching
0%
No client-side caching
Data versioning support
0%
No versioning
Live backups
Hot backup supported

Distribution

Cluster Re-balancing
50%
No description available
Data Distribution
Data sharding supported
High-Availability
HA mechanisms available
Query Distribution
Distributed query execution
Replication support
Replication available

Developer Experience

Data types defined
0%
Single data type (strings)
Logging/Auditing
Event logging supported
Object-Graph Mapper
OGM/ORM available
Reactive programming
Reactive streams supported
Documentation up-to-date
Docs current with latest version
Binary protocol
0%
Text-based protocols only
CLI
Command-line interface
GUI
Visual interface available

Data Model

Multi-database
Multi-model database
Graph-native data
0%
Graph abstraction layer
REST API
REST endpoint available
Query Language
Standard query language (Cypher/Gremlin)

Transactions

Granular locking
0%
No granular locking
Multiple isolation levels
Multiple isolation levels
Read committed transaction
Read committed available
Transaction support
50%
No description available

Schema & Security

Constraints
0%
No constraints
Schema support
0%
Schema-less
Secondary indexes
Secondary indexes supported
Server side procedures
Stored procedures supported
Triggers
Event triggers supported
Authentication
Authentication supported
Authorization
Role-based access control
Data encryption
Data encryption supported
Sources 8 references

Protocols Gremlin (WebSocket), HTTP/REST, Native binary

Gremlin API is WebSocket (confirmed by the 101-upgrade error path in the Gremlin FAQ) and the default access mode for all APIs is an HTTPS gateway (HTTP/REST); rejected pass_B's justification for Native binary (Cassandra/MongoDB wire compatibility, which explicitly reuse standard, non-proprietary protocols the vocabulary has no tag for) but added Native binary anyway for a different, undisputed reason neither pass raised: the SQL/Core API's proprietary TCP 'direct mode', which only the .NET and Java SDKs support and which Microsoft does not publish a wire spec for; the port table shows direct mode is not offered for the Graph API.

License Proprietary

Confirms the current value. Cosmos DB is a closed-source, commercially licensed Microsoft cloud service; no source or license file is published.

  • Azure Cosmos DB is a fully managed, cloud-native NoSQL database designed to deliver ultra-low latency and elastic scalability at a global scale.
    Azure Cosmos DB | Microsoft Azure · reviewed 2026-08-02
  • Written in C++ Supported Languages C#, Go, Java, JavaScript, Python Operating System Windows License Proprietary
    Cosmos DB · Database of Databases · reviewed 2026-08-02

Released 2014-08

Corrected from 2017-05. That date is Cosmos DB's rebrand/GA, but Microsoft's own account is that the same underlying engine ("Project Florence", 2010) first reached the public as Azure DocumentDB, in preview, in August 2014; DocumentDB became generally available in 2015 and was renamed/expanded into Cosmos DB in May 2017. Treated as a rename per the brief's guidance rather than a new product.

Language C++

No primary Microsoft source discloses the implementation language of this closed-source service. Only a third-party database encyclopedia was found; treat as a lead rather than a confirmed fact.

  • Written in C++ Supported Languages C#, Go, Java, JavaScript, Python Operating System Windows License Proprietary
    Cosmos DB · Database of Databases · reviewed 2026-08-02