What is Azure Cosmos DB?

Azure Cosmos DB is a globally distributed, multi-model database service that enables you to create and interact with modern applications at any scale. It provides a highly available, low-latency, and globally consistent database experience. Cosmos DB is designed for applications that require rapid development, elastic scalability, and high availability, regardless of where your users are located.

Key Features and Benefits

  • Global Distribution: Distribute your data across any number of Azure regions, offering unparalleled availability and disaster recovery.
  • Multi-Model Support: Work with data in various models, including document, key-value, graph, and column-family, all within a single service.
  • Guaranteed Throughput and Latency: Provides predictable performance with guaranteed low latency and high throughput.
  • Elastic Scalability: Scale your database throughput and storage up or down on demand, independently for each region.
  • Five Consistency Levels: Choose from a range of consistency models, from strong consistency to eventual consistency, to meet your application's needs.
  • Multiple APIs: Integrate with existing applications using familiar APIs like SQL (Core) API, MongoDB API, Cassandra API, Gremlin API, and Table API.

Core Concepts

Understanding these core concepts is crucial for effectively using Azure Cosmos DB:

  • Account: The top-level resource in Azure Cosmos DB. It contains databases, containers, and items.
  • Database: A container for containers.
  • Container: A schema-agnostic container for items. It's the unit of horizontal scalability. Items within a container are partitioned based on a partition key.
  • Item: The basic unit of data storage in a container. In the SQL (Core) API, items are JSON documents.
  • Partition Key: A property within an item that determines the physical partition where the item is stored. Choosing an effective partition key is vital for performance and scalability.
  • Throughput: Measured in Request Units (RUs) per second, representing the measure of database throughput. You can provision throughput at the container or database level.

Important Consideration: Partition Key Selection

The choice of a partition key significantly impacts the performance, scalability, and availability of your data. A good partition key distributes requests and storage evenly across physical partitions, avoiding hot partitions.

When to Use Azure Cosmos DB

Azure Cosmos DB is an excellent choice for a wide range of applications, including:

  • IoT Data: Ingest and process massive amounts of telemetry data from IoT devices.
  • Gaming: Store player data, leaderboards, and game state with low latency worldwide.
  • E-commerce: Manage product catalogs, customer profiles, and shopping carts for a global audience.
  • Web and Mobile Applications: Provide a responsive and scalable backend for modern web and mobile experiences.
  • Personalization: Deliver personalized content and recommendations based on user data.

Get Started Today

Explore the quickstarts and tutorials to begin building your first application with Azure Cosmos DB. Leverage its power to build responsive, always-on applications at global scale.

For detailed information, refer to the official Azure Cosmos DB documentation.

Supported APIs

Azure Cosmos DB offers flexibility by supporting multiple APIs for data interaction:

  • SQL (Core) API: The native API for Cosmos DB, offering JSON document querying with rich SQL-like syntax.
  • MongoDB API: A compatibility layer for MongoDB applications, allowing you to migrate MongoDB workloads to Cosmos DB.
  • Cassandra API: For applications built on Apache Cassandra, enabling migration and integration.
  • Gremlin API: Supports graph databases using the Apache TinkerPop Gremlin language.
  • Table API: For applications using Azure Table storage, providing a compatible interface.