Quickstart: Azure Cosmos DB for Table for .NET
APPLIES TO: Table
This quickstart shows how to get started with the Azure Cosmos DB for Table from a .NET application. The Azure Cosmos DB for Table is a schemaless data store allowing applications to store structured table data in the cloud. You'll learn how to create tables, rows, and perform basic tasks within your Azure Cosmos DB resource using the Azure.Data.Tables Package (NuGet).
Note
The example code snippets are available on GitHub as a .NET project.
API for Table reference documentation | Azure.Data.Tables Package (NuGet)
Prerequisites
- An Azure account with an active subscription. Create an account for free.
- GitHub account
- An Azure account with an active subscription. Create an account for free.
- Azure Developer CLI
- Docker Desktop
Setting up
Deploy this project's development container to your environment. Then, use the Azure Developer CLI (azd) to create an Azure Cosmos DB for Table account and deploy a containerized sample application. The sample application uses the client library to manage, create, read, and query sample data.
Important
GitHub accounts include an entitlement of storage and core hours at no cost. For more information, see included storage and core hours for GitHub accounts.
Open a terminal in the root directory of the project.
Authenticate to the Azure Developer CLI using
azd auth login
. Follow the steps specified by the tool to authenticate to the CLI using your preferred Azure credentials.azd auth login
Use
azd init
to initialize the project.azd init
During initialization, configure a unique environment name.
Tip
The environment name will also be used as the target resource group name. For this quickstart, consider using
msdocs-cosmos-db
.Deploy the Azure Cosmos DB account using
azd up
. The Bicep templates also deploy a sample web application.azd up
During the provisioning process, select your subscription and desired location. Wait for the provisioning process to complete. The process can take approximately five minutes.
Once the provisioning of your Azure resources is done, a URL to the running web application is included in the output.
Deploying services (azd deploy) (✓) Done: Deploying service web - Endpoint: <https://[container-app-sub-domain].azurecontainerapps.io> SUCCESS: Your application was provisioned and deployed to Azure in 5 minutes 0 seconds.
Use the URL in the console to navigate to your web application in the browser. Observe the output of the running app.
Install the client library
The client library is available through NuGet, as the Microsoft.Azure.Cosmos
package.
Open a terminal and navigate to the
/src/web
folder.cd ./src/web
If not already installed, install the
Azure.Data.Tables
package usingdotnet add package
.dotnet add package Azure.Data.Tables
Also, install the
Azure.Identity
package if not already installed.dotnet add package Azure.Identity
Open and review the src/web/Cosmos.Samples.Table.Quickstart.Web.csproj file to validate that the
Microsoft.Azure.Cosmos
andAzure.Identity
entries both exist.
Code examples
The sample code described in this article creates a table named adventureworks
. Each table row contains the details of a product such as name, category, quantity, and a sale indicator. Each product also contains a unique identifier.
You'll use the following API for Table classes to interact with these resources:
TableServiceClient
- This class provides methods to perform service level operations with Azure Cosmos DB for Table.TableClient
- This class allows you to interact with tables hosted in the Azure Cosmos DB table API.TableEntity
- This class is a reference to a row in a table that allows you to manage properties and column data.
Authenticate the client
From the project directory, open the Program.cs file. In your editor, add a using directive for Azure.Data.Tables
.
using Azure.Data.Tables;
Define a new instance of the TableServiceClient
class using the constructor, and Environment.GetEnvironmentVariable
to read the connection string you set earlier.
// New instance of the TableClient class
TableServiceClient tableServiceClient = new TableServiceClient(Environment.GetEnvironmentVariable("COSMOS_CONNECTION_STRING"));
Create a table
Retrieve an instance of the TableClient
using the TableServiceClient
class. Use the TableClient.CreateIfNotExistsAsync
method on the TableClient
to create a new table if it doesn't already exist. This method will return a reference to the existing or newly created table.
// New instance of TableClient class referencing the server-side table
TableClient tableClient = tableServiceClient.GetTableClient(
tableName: "adventureworks"
);
await tableClient.CreateIfNotExistsAsync();
Create an item
The easiest way to create a new item in a table is to create a class that implements the ITableEntity
interface. You can then add your own properties to the class to populate columns of data in that table row.
// C# record type for items in the table
public record Product : ITableEntity
{
public string RowKey { get; set; } = default!;
public string PartitionKey { get; set; } = default!;
public string Name { get; init; } = default!;
public int Quantity { get; init; }
public bool Sale { get; init; }
public ETag ETag { get; set; } = default!;
public DateTimeOffset? Timestamp { get; set; } = default!;
}
Create an item in the collection using the Product
class by calling TableClient.AddEntityAsync<T>
.
// Create new item using composite key constructor
var prod1 = new Product()
{
RowKey = "68719518388",
PartitionKey = "gear-surf-surfboards",
Name = "Ocean Surfboard",
Quantity = 8,
Sale = true
};
// Add new item to server-side table
await tableClient.AddEntityAsync<Product>(prod1);
Get an item
You can retrieve a specific item from a table using the TableClient.GetEntityAsync<T>
method. Provide the partitionKey
and rowKey
as parameters to identify the correct row to perform a quick point read of that item.
// Read a single item from container
var product = await tableClient.GetEntityAsync<Product>(
rowKey: "68719518388",
partitionKey: "gear-surf-surfboards"
);
Console.WriteLine("Single product:");
Console.WriteLine(product.Value.Name);
Query items
After you insert an item, you can also run a query to get all items that match a specific filter by using the TableClient.Query<T>
method. This example filters products by category using Linq syntax, which is a benefit of using typed ITableEntity
models like the Product
class.
Note
You can also query items using OData syntax. You can see an example of this approach in the Query Data tutorial.
// Read multiple items from container
var prod2 = new Product()
{
RowKey = "68719518390",
PartitionKey = "gear-surf-surfboards",
Name = "Sand Surfboard",
Quantity = 5,
Sale = false
};
await tableClient.AddEntityAsync<Product>(prod2);
var products = tableClient.Query<Product>(x => x.PartitionKey == "gear-surf-surfboards");
Console.WriteLine("Multiple products:");
foreach (var item in products)
{
Console.WriteLine(item.Name);
}
Run the code
This app creates an Azure Cosmos DB Table API table. The example then creates an item and then reads the exact same item back. Finally, the example creates a second item and then performs a query that should return multiple items. With each step, the example outputs metadata to the console about the steps it has performed.
To run the app, use a terminal to navigate to the application directory and run the application.
dotnet run
The output of the app should be similar to this example:
Single product name:
Yamba Surfboard
Multiple products:
Yamba Surfboard
Sand Surfboard
Clean up resources
When you no longer need the Azure Cosmos DB for Table account, you can delete the corresponding resource group.
Use the az group delete
command to delete the resource group.
az group delete --name $resourceGroupName
Next steps
In this quickstart, you learned how to create an Azure Cosmos DB for Table account, create a table, and manage entries using the .NET SDK. You can now dive deeper into the SDK to learn how to perform more advanced data queries and management tasks in your Azure Cosmos DB for Table resources.