LINQ to CockroachDB Data

This article illustrates using LINQ to access tables within the CockroachDB via the CData ADO.NET Data Provider for CockroachDB. 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 CockroachDB Data Source".

4. Enter your data source connection information.

   Set the following to connect to CockroachDB.

   • Server: The host name or IP address of the server.
   • Port: The port number of the CockroachDB server. If not specified, the default port is 26257.
   • Database: The name of the Cockroach database. If not specified, you connect to the user's default database.
   • User: The Cockroach DB user account used to authenticate.
   • Password: The password used to authenticate the user.

   Below is a typical connection string:

   User=root;Password=root;Database=system;Server=localhost;Port=26257

👁 Required connection properties for the data source. (QuickBooks is shown.)

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

CockroachDBEntities context = new CockroachDBEntities();

var ordersQuery = from orders in context.Orders
 select orders;

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

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