Azure Cosmos DB Blog
The latest news, updates and technical insights from the Azure Cosmos DB team
Latest posts
Build 2025 Preview: Transform Your AI Apps and Agents with Azure Cosmos DB
Microsoft Build is less than a week away, and the Azure Cosmos DB team will be out in force to showcase the newest features and capabilities for building AI apps and agents with scalable, fast, high-performance data. Whether you’re in person at the Seattle Convention Center or watching the live or on-demand digital show, we can’t wait to show you what we’ve been up to. Add these breakout, demo, and labs sessions to your Build schedule: Monday, May 19th 🗓️ 11:45am PT: What’s New in Microsoft Databases: Empowering AI-Driven App Dev (BRK204) with Shireesh Thota, Corporate VP of Engineering – Databases...
Fabric Mirroring for Azure Cosmos DB: Public Preview Refresh Now Live with New Features
We’re thrilled to announce the latest refresh of Fabric Mirroring for Azure Cosmos DB, now available with several powerful new features that enhance your data analytics infrastructure. This update significantly improves the experience, making it easier than ever to replicate your Azure Cosmos DB data into OneLake in Microsoft Fabric—giving you more control and flexibility over your mirrored databases. New Features Entra ID Authentication Support for Source Connections Azure Cosmos DB Mirroring now supports authentication via Microsoft Entra ID (formerly Azure AD), in addition to account keys. This enhancem...
Azure Cosmos DB with DiskANN Part 4: Stable Vector Search Recall with Streaming Data
Vector search with Azure Cosmos DB In Part 1 and Part 2 of this series, we explored vector search with Azure Cosmos DB and best practices for scaling it to 1 billion vector datasets while maintaining low query latency. In Part 3, we saw how we can create efficient sharded DiskANN indices for multi-tenant apps. In Part 4, we’ll look at the effect that streaming ingestion, a stream of inserts, deletes, and replaces of vectors in the database, has on the quality of the vector index. This is unlike the often reported single-shot ingestion where data is ingested once in bulk and recall is measured at the end whe...
General Availability for Data API in vCore-based Azure Cosmos DB for MongoDB
Title: General Availability for Data API in vCore-based Azure Cosmos DB for MongoDB We’re excited to announce the general availability of the Data API for vCore-based Azure Cosmos DB for MongoDB! Overview The Data API is a RESTful HTTPS interface that enables developers to interact with their MongoDB data hosted in vCore-based Azure Cosmos DB directly from their applications—no drivers or complex query logic required. It offers a simple, efficient way to connect your MongoDB data with web apps, mobile apps, and tools like Power BI. At launch, the Data API supports the following read operations: ...
Getting Started with Azure Cosmos DB Using the Python SDK
If you're new to Azure Cosmos DB and looking to build applications with Python, you're in the right place. I’ve created a four-part video series designed to take you from the basics to practical, real-world querying techniques—no prior experience required. Whether you’re setting up your first database, learning how to model your data, or optimizing your queries, this series will help you build confidence with each step. This blog post is your companion guide. It introduces key concepts, outlines what each video covers, and provides helpful context so you can follow along more effectively. Whether you're a stud...
Fast, Accurate, and Affordable: Sharded DiskANN for Multitenant Vector Search in Azure Cosmos DB
Introduction Azure Cosmos DB now includes Sharded DiskANN, a powerful capability that optimized for large-scale multitenant apps by splitting a DiskANN index into smaller, more performant pieces. When you specify a VectorIndexShardKey in your container’s indexing policy, Azure Cosmos DB creates multiple DiskANN indexes, one for each unique value of the selected document property. This can provide multiple benefits including: Use Cases Sharded DiskANN is especially valuable in scenarios where data isolation and targeted search are essential, such as: How is it different than...
Azure Cosmos DB Conf 2025 Recap: AI, Apps & Scale
On April 15, 2025, developers from around the world came together for Azure Cosmos DB Conf 2025—a free virtual event co-hosted by Microsoft and the vibrant Azure Cosmos DB community. From early-morning keynotes to lightning talks and live demos, the event was packed with fresh insights, expert guidance, and real-world examples of how developers are solving complex challenges with Azure Cosmos DB. This year’s sessions explored a broad spectrum of themes, including AI-powered workloads, real-time analytics, cost optimization, open-source tools, hybrid and vector search, and data security. Whether attendees were new...
Azure Cosmos DB with DiskANN Part 2: Scaling to 1 Billion Vectors with <100ms Search Latency
Introduction In the first part of our series on Azure Cosmos DB Vector Search with DiskANN, we explored the fundamentals of vector indexing and search capabilities using Azure Cosmos DB for NoSQL and demonstrated a few early performance and cost characteristics. In Part 2, we’ll demonstrate how to scale to 1 billion vector datasets, while maintaining a query latency of under 100 milliseconds with > 90% recall, all in a cost-effective manner. Along the way, we will review concepts like partitioning for managing large-scale vector data in Azure Cosmos DB, along with optimizations & best practices for faster...
Introducing Region Selection in Azure Cosmos DB Data Explorer for NoSQL Accounts
You asked—we delivered! Users can now manually select the region Data Explorer sends requests to! When you use Entra Authentication with NoSQL accounts, you can now enable the Region Selection option in settings. This new capability gives you precise control over where your requests are sent, helping you test, troubleshoot, and optimize performance by targeting a specific Azure region directly from the portal. When you select a specific region, the Azure Cosmos DB client disables endpoint discovery and sends requests only to that region. This works similarly to using a regional connection string at https://...