whichdb
vs

Azure DocumentDB vs DocumentDB (open-source, PostgreSQL-based)

Azure DocumentDB: Microsoft's managed MongoDB-compatible service, built on the open-source DocumentDB engine. DocumentDB (open-source, PostgreSQL-based): MIT-licensed, MongoDB-compatible document engine built as PostgreSQL extensions, run by the Linux Foundation.

key differences

  • Licensing: Azure DocumentDB is proprietary (Proprietary Azure service (engine is MIT-licensed DocumentDB)); DocumentDB (open-source, PostgreSQL-based) is open source (permissive) (MIT License).
  • Azure DocumentDB is built for larger datasets (≤ 1 PB) than DocumentDB (open-source, PostgreSQL-based) (≤ 10 TB).
  • Horizontal scaling is native in Azure DocumentDB and none in DocumentDB (open-source, PostgreSQL-based).
  • Only Azure DocumentDB has encryption at rest.

choose azure-documentdb for

  • +MongoDB migrations to Azure without SSPL
  • +Content management and catalog backends with complex aggregations
  • +RAG applications storing embeddings next to documents

best at · OLTP, Content, Vector search

choose documentdb-postgres for

  • +Self-hosted MongoDB-compatible database without SSPL
  • +Migrating MongoDB apps onto PostgreSQL infrastructure
  • +Document plus vector storage for RAG on Kubernetes
  • +Local development matching Azure DocumentDB

best at · OLTP, Content, Vector search

Azure DocumentDBMicrosoft's managed MongoDB-compatible service, built on the open-source DocumentDB engine.
DocumentDB (open-source, PostgreSQL-based)MIT-licensed, MongoDB-compatible document engine built as PostgreSQL extensions, run by the Linux Foundation.
overview
Primary model
Document
Document
Also supports
Vector, Spatial
Vector, Spatial
Type
Managed service
Database engine
Status
Active
Active
Developer
Microsoft
DocumentDB project (Linux Foundation; originated at Microsoft)
First release
2023
2025
Latest version
–
1.0 (Oct 19, 2026)
License
ProprietaryProprietary Azure service (engine is MIT-licensed DocumentDB)
Open source (permissive)MIT License
Free tier
✓
✓
popularity
WhichDB Score
0.0
5.4
Rank
#692
#386
GitHub stars
–
3.5K
Stack Overflow questions
–
–
scale & guarantees
Comfortable data size
Large (≤ 1 PB)
Medium (≤ 10 TB)
Horizontal scaling
Native
None
Multi-region
Read replicas
Read replicas
ACID
Full
Full
Consistency
Strong
Strong
Schema
Schemaless
Schemaless
Architecture
Distributed, Primary replica
Primary replica, Client server
deployment
Self-hosted
—
✓
Vendor-managed cloud
✓
—
Serverless
—
—
Embedded
—
—
Edge
—
—
Clouds
Azure
–
capabilities
Transactions
✓
✓
Joins
✓
✓
Secondary indexes
✓
✓
Full-text search
✓
✓
Vector search
✓
✓
Geospatial
✓
✓
JSON
✓
✓
Change data capture
—
—
Triggers
—
—
Stored procedures
—
—
Materialized views
—
—
TTL / expiry
✓
✓
Pub/Sub
—
—
Columnar storage
—
—
In-memory
—
—
Durable persistence
✓
✓
Compression
—
—
Encryption at rest
✓
—
Role-based access
✓
✓
Time travel
—
—
Branching
—
—
Online schema changes
✓
✓
Streaming ingest
—
—
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
MongoDB Query API (MQL), Aggregation pipeline
MongoDB Query API (MQL), Aggregation pipeline, SQL (via PostgreSQL)
Client languages
C#, Java, Python, JavaScript, Go
Java, Python, JavaScript, Go, C#, Rust
Best for
OLTP, Content, Vector search, RAG
OLTP, Content, Vector search, RAG
Add more to this comparisonNot sure either fits? Try smart match

Azure DocumentDB vs DocumentDB (open-source, PostgreSQL-based): FAQ

What is the difference between Azure DocumentDB and DocumentDB (open-source, PostgreSQL-based)?

Azure DocumentDB: Microsoft's managed MongoDB-compatible service, built on the open-source DocumentDB engine. DocumentDB (open-source, PostgreSQL-based): MIT-licensed, MongoDB-compatible document engine built as PostgreSQL extensions, run by the Linux Foundation. Licensing: Azure DocumentDB is proprietary (Proprietary Azure service (engine is MIT-licensed DocumentDB)); DocumentDB (open-source, PostgreSQL-based) is open source (permissive) (MIT License). Azure DocumentDB is built for larger datasets (≤ 1 PB) than DocumentDB (open-source, PostgreSQL-based) (≤ 10 TB). Horizontal scaling is native in Azure DocumentDB and none in DocumentDB (open-source, PostgreSQL-based).

When should I choose Azure DocumentDB over DocumentDB (open-source, PostgreSQL-based)?

Choose Azure DocumentDB for MongoDB migrations to Azure without SSPL; content management and catalog backends with complex aggregations; and RAG applications storing embeddings next to documents. Choose DocumentDB (open-source, PostgreSQL-based) for self-hosted MongoDB-compatible database without SSPL, migrating MongoDB apps onto PostgreSQL infrastructure and document plus vector storage for RAG on Kubernetes.

Is Azure DocumentDB or DocumentDB (open-source, PostgreSQL-based) more popular?

DocumentDB (open-source, PostgreSQL-based) ranks #386 on the WhichDB Score (5.4/100) and Azure DocumentDB ranks #692 (0.0/100). Popularity is not fit: check the requirements that matter for your project.

Are Azure DocumentDB and DocumentDB (open-source, PostgreSQL-based) open source?

No. Azure DocumentDB is proprietary, closed-source software. Yes. DocumentDB (open-source, PostgreSQL-based) is open source. License: MIT License.