Azure Cosmos DB
Azure Cosmos DB is a globally distributed, multi-model database service. It provides a rich set of features designed for modern application development, including guaranteed low latency, high availability, and elastic scalability.
Key Features:
- Globally Distributed: Replicate your data across any number of Azure regions.
- Multi-Model: Supports document, key-value, graph, and column-family data models.
- Guaranteed Throughput & Latency: Offers predictable performance with Service Level Agreements (SLAs).
- Elastic Scalability: Scale throughput and storage independently and on demand.
- Multiple APIs: Works with familiar APIs like SQL (Core), MongoDB, Cassandra, Gremlin, and Table.
Getting Started with Azure Cosmos DB
This section guides you through the initial steps of creating and configuring an Azure Cosmos DB account.
1. Create a Cosmos DB Account
You can create an Azure Cosmos DB account using the Azure portal, Azure CLI, or Azure PowerShell.
Using the Azure Portal:
- Navigate to the Azure portal.
- Click "Create a resource".
- Search for "Azure Cosmos DB" and select it.
- Click "Create".
- Configure the necessary settings, including the API, subscription, resource group, region, and capacity mode.
- Click "Review + create" and then "Create".
Tip: For development and testing, you can use the free tier or a local emulator to experiment without incurring costs.
2. Choose an API
Azure Cosmos DB supports multiple APIs, allowing you to use the database with your existing knowledge and tools:
- Core (SQL) API: The default and most commonly used API, offering a JSON document database with a rich query language.
- MongoDB API: Compatible with MongoDB applications, allowing you to migrate existing MongoDB workloads to Azure.
- Cassandra API: For workloads built on Apache Cassandra.
- Gremlin API: For graph database workloads.
- Table API: Compatible with Azure Table storage.
3. Connect to Your Cosmos DB Account
Once your account is created, you'll need to obtain connection strings and keys to interact with your data. These can be found in the "Keys" section of your Cosmos DB resource in the Azure portal.
# Example using Azure CLI to get connection string
az cosmosdb keys list --name mycosmosdbaccount --resource-group myresourcegroup --type connection-strings
Common Use Cases
Azure Cosmos DB is ideal for a wide range of applications:
- IoT data: Ingesting and processing high volumes of telemetry data.
- Gaming: Storing player profiles, game state, and leaderboards.
- Web and mobile applications: Powering user profiles, product catalogs, and shopping carts.
- Real-time analytics: Providing low-latency access to data for dashboards and reporting.
Data Modeling and Partitioning
Effective data modeling and partitioning are crucial for performance in Azure Cosmos DB. Choose a logical partition key that distributes requests evenly across physical partitions.
Important: A well-chosen partition key is essential for scaling and performance. Avoid hot partitions by ensuring your partition key has high cardinality and distributes data evenly.