Ready to get started?

Learn more about the CData ADO.NET Provider for Cosmos DB or download a free trial:

Download Now

LINQ to Cosmos DB Data

LINQ provides general-purpose query facilities in .NET Framework 3.0 and above and provides one easy way to programmatically access data through from CData ADO.NET Data Providers. This example uses LINQ to access information from the Cosmos DB Data Provider.

This article demonstrates how to use LINQ to access Cosmos DB tables through the CData ADO.NET Data Provider for Cosmos DB. To do this you will LINQ to Entity Framework, which is used to generate the connection and can be used with any CData ADO.NET Data Providers to access data via LINQ.

See the help documentation for a guide to setting up an EF 6 project to use the provider.

  1. In a new project in Visual Studio, right-click on the project and choose to add a new item. Add an ADO.NET Entity Data Model.
  2. Choose EF Designer from Database and click Next.
  3. Add a new Data Connection, and change your data source type to "CData Cosmos DB Data Source".
  4. Enter your data source connection information.

    To obtain the connection string needed to connect to a Cosmos DB account using the SQL API, log in to the Azure Portal, select Azure Cosmos DB, and select your account. In the Settings section, click Connection String and set the following values:

    • AccountEndpoint: The Cosmos DB account URL from the Keys blade of the Cosmos DB account
    • AccountKey: In the Azure portal, navigate to the Cosmos DB service and select your Azure Cosmos DB account. From the resource menu, go to the Keys page. Find the PRIMARY KEY value and set AccountKey to this value.

    Below is a typical connection string:

    AccountEndpoint=myAccountEndpoint;AccountKey=myAccountKey;
  5. If saving your entity connection to App.Config, set an entity name. In this example we are setting CosmosDBEntities as our entity connection in App.Config.
  6. Enter a model name and select any tables or views you would like to include in the model.

Using the entity you created, you can now perform select , update, delete, and insert commands. For example:

CosmosDBEntities context = new CosmosDBEntities(); var customersQuery = from customers in context.Customers select customers; foreach (var result in customersQuery) { Console.WriteLine("{0} {1} ", result.id, result.City); }

See "LINQ and Entity Framework" chapter in the help documentation for example queries of the supported LINQ.