LINQ to Placid Data

This article illustrates using LINQ to access tables within the Placid via the CData ADO.NET Data Provider for Placid. To achieve this, we will use LINQ to Entity Framework, which facilitates the generation of connections and can be seamlessly employed with any CData ADO.NET Data Providers to access data through 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 Placid Data Source".

4. Enter your data source connection information.

   Placid uses API Key authentication to control access to the API. API tokens are project-specific and can be obtained from your project settings on placid.app.

   Using API Key Authentication

   To obtain your API key, log in to placid.app, navigate to your project, open the project settings, and generate an API token from the API section. Note that each API token is scoped to a specific project.

   After setting the following connection properties, you are ready to connect:

   • AuthScheme: Set this to APIKey.
   • APIKey: Set this to your Placid project API token.

   Example connection string:

   Profile=C:\profiles\Placid.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_project_api_token';
   

   Below is a typical connection string:

   Profile=C:\profiles\Placid.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_project_api_token';


5. If saving your entity connection to App.Config, set an entity name. In this example we are setting APIEntities 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 commands. For example:

APIEntities context = new APIEntities();

var collectionsQuery = from collections in context.Collections
  select collections;

foreach (var result in collectionsQuery) {
  Console.WriteLine("{0} {1} ", result.Id, result.);
}

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