MSDN Documentation

Introduction to Azure Cosmos DB

Azure Cosmos DB is a globally distributed, multi-model database service from Microsoft Azure. It's designed to enable developers to build highly responsive and always-on applications with ease. Cosmos DB offers a unique combination of features that make it a compelling choice for modern cloud-native applications.

What is Azure Cosmos DB?

Azure Cosmos DB is Microsoft's globally distributed, multi-model database service. It provides a fully managed platform for modern application development, offering robust features like:

• Global Distribution: Replicate your data across any number of Azure regions worldwide with just a few clicks. This ensures low latency for users anywhere in the world and high availability.
• Multi-Model Capabilities: Supports various data models, including document, key-value, graph, and column-family, through distinct APIs.
• Elastic Scalability: Independently and elastically scale throughput and storage to meet application demands.
• Guaranteed Low Latency: Offers predictable performance with guaranteed low latencies for reads and writes.
• Guaranteed High Availability: Provides a 99.999% availability SLA.
• Schema-Agnostic: No need for schema design or migrations for many workloads.

Key Concepts

Understanding the core concepts of Azure Cosmos DB is crucial for effective utilization. The key hierarchical components are:

1. Accounts: The top-level resource for Cosmos DB. You can have multiple accounts for different applications or environments.
2. Databases: A container for collections or tables.
3. Containers (or Tables): The fundamental unit of scalability for metadata, JSON documents, or entities. Each container has its own provisioned throughput and storage.
4. Items (or Documents/Entities): The atomic data entries within a container.

Supported APIs

Cosmos DB offers a variety of APIs to support different application development paradigms:

• Core (SQL) API: A powerful, JSON document database with schema-agnostic data indexing and rich SQL query capabilities.
• MongoDB API: API compatibility with MongoDB, enabling applications to leverage existing MongoDB drivers and tools.
• Cassandra API: API compatibility with Apache Cassandra, allowing developers to use existing Cassandra tools.
• Gremlin API: A graph database API that supports Apache TinkerPop Gremlin, ideal for complex relationship data.
• Table API: API compatibility with Azure Table Storage, for applications using that service.

When to Use Azure Cosmos DB?

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

• IoT data: Ingesting and processing high volumes of data from Internet of Things devices.
• Web and Mobile Apps: Powering backend services for scalable, responsive web and mobile applications.
• Gaming: Storing player data, leaderboards, and session information with low latency.
• E-commerce: Managing product catalogs, user profiles, and order information.
• Real-time Analytics: Processing and analyzing data streams in near real-time.

Getting Started

To start using Azure Cosmos DB:

1. Create an Azure account if you don't have one.
2. Navigate to the Azure portal and create an Azure Cosmos DB account.
3. Choose the API that best suits your application's needs.
4. Create a database and a container (or table).
5. Start adding data and querying it using the chosen API.

For detailed guidance, refer to the official Azure Cosmos DB documentation and the various tutorials and quickstarts available.