Azure Cosmos DB for NoSQL vs Milvus
Azure Cosmos DB for NoSQL
azure.microsoft.comMilvus
milvus.ioSide by side
| Figure | Azure Cosmos DB for NoSQL | Milvus |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 10 | 1 |
| Spec score · Ai Databases | 8.1 (#12) | 8.3 (#8) |
| Spec score · Database Software | 8.1 (#42) | 8.2 (#39) |
| Free plan | Yes | Yes |
| Integrations | Change feed supports event-driven architectures and streaming pipelines using Azure Functions and Spark. | The integrations documentation lists tools including LangChain, LlamaIndex, Haystack, DSPy, Dify, Langflow, OpenAI, Cohere, and HuggingFace. |
| Search | It offers built-in vector and hybrid similarity search for workloads including RAG and AI agents. | Milvus supports approximate nearest neighbor, filtering, range, hybrid, and full-text search, plus reranking, fetch, and query operations. |
| Security | Microsoft recommends private endpoints, disabling public network access, and client-side encryption with Always Encrypted for sensitive data. | Milvus documents user authentication, TLS encryption for gRPC and REST traffic, and role-based access control. |
| What it does | Azure Cosmos DB for NoSQL is a fully managed cloud database using a schema-agnostic JSON document model with SQL-like querying. | Milvus is an open-source vector database developed by Zilliz for high-performance, scalable vector search. |
Plans
Azure Cosmos DB for NoSQL
- Free tierFree
- 30-day free trialPriced on request
- Standard provisioned throughputPriced on request
- Standard provisioned throughputPrice not published
- Autoscale provisioned throughputPriced on request
- Autoscale provisioned throughputPrice not published
- ServerlessPriced on request
- ServerlessPrice not published
- Azure Cosmos DB free tierFree
- Azure Cosmos DB for NoSQL — standard provisioned throughputPrice not published
In their own words
Azure Cosmos DB for NoSQL
Azure Cosmos DB for NoSQL is a fully managed cloud database built around schema-agnostic JSON documents and SQL-like querying. It supports global data distribution, multi-region writes, and automatic failover, with configurable consistency controls and transactions. Search includes vector and hybrid similarity capabilities for workloads such as retrieval-augmented generation and AI agents. Throughput can use standard provisioned, autoscale provisioned, or serverless models. The service lists SDKs for.NET, Java, JavaScript/Node.js, Python, Go, and Rust. Its change feed can support event-driven architectures and streaming pipelines using Azure Functions and Spark; no-ETL analytical workflows are available through Azure Synapse Link or Fabric mirroring. Microsoft states that NoSQL data has service-level agreements including less than 10 millisecond read and write latency and 99.999 percent availability. A free tier includes 1,000 RU/s and 25 GB of storage for one account per Azure subscription, and a 30-day trial is listed. The Azure Cosmos DB emulator provides a no-cost local development environment for Windows or Linux. The pricing page notes that the selected compute pricing model and API cannot be changed after selection.
Milvus
Milvus is an open-source vector database from Zilliz for GenAI and scalable vector search. It supports approximate-nearest-neighbor, filtered, range, hybrid, and full-text search, along with reranking, fetch, and query operations. Metadata filtering, sparse vectors, and index types including HNSW, IVF, FLAT, DiskANN, and SCANN are documented. Deployment choices are Milvus Lite as a Python library, Standalone as a single-machine server, and Distributed on Kubernetes. Documentation recommends Lite for up to a few million vectors, Standalone up to 100 million, and Distributed for 100 million to tens of billions. Lite can run locally without a cloud service for private or sensitive data; an online upgrade from Standalone to a cluster is not currently supported. Official interfaces include REST plus Python, Go, Java, Node.js, and C++ APIs or SDKs. C# is contributed by Microsoft and Rust is under development. Security documentation covers authentication, TLS for gRPC and REST, and role-based access control at collection, database, and instance levels. The Apache 2.0 software is free, and Zilliz Cloud is offered as a managed option.