LINQ to Oracle Data

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

4. Enter your data source connection information.

   To connect to Oracle, you'll first need to update your PATH variable and ensure it contains a folder location that includes the native DLLs. The native DLLs can be found in the lib folder inside the installation directory. Once you've done this, set the following to connect:

   • Port: The port used to connect to the server hosting the Oracle database.
   • User: The user Id provided for authentication with the Oracle database.
   • Password: The password provided for authentication with the Oracle database.
   • Service Name: The service name of the Oracle database.

   Below is a typical connection string:

   User=myuser;Password=mypassword;Server=localhost;Port=1521;

👁 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 OracleOCIEntities 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:

OracleOCIEntities context = new OracleOCIEntities();

var customersQuery = from customers in context.Customers
 select customers;

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

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