Working with AlloyDB Data in LINQPad

The CData ADO.NET Provider for AlloyDB enables you to use standard ADO.NET interfaces like LINQ and the Entity Framework to work with AlloyDB data. This article will demonstrate the process of establishing a connection from LINQPad and executing LINQ queries.

Create the Data Model

After downloading and installing both the provider and LINQPad, create a new class library project within Visual Studio.

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

1. Right-click your project and click Add -> New Item -> ADO.NET Entity Data Model. In the resulting dialog, select Code First from database. Click New Connection and specify the connection string options in the resulting wizard.

   The following connection properties are usually required in order to connect to AlloyDB.

   • Server: The host name or IP of the server hosting the AlloyDB database.
   • User: The user which will be used to authenticate with the AlloyDB server.
   • Password: The password which will be used to authenticate with the AlloyDB server.

   You can also optionally set the following:

   • Database: The database to connect to when connecting to the AlloyDB Server. If this is not set, the user's default database will be used.
   • Port: The port of the server hosting the AlloyDB database. This property is set to 5432 by default.

   Authenticating with Standard Authentication

   Standard authentication (using the user/password combination supplied earlier) is the default form of authentication.

   No further action is required to leverage Standard Authentication to connect.

   Authenticating with pg_hba.conf Auth Schemes

   There are additional methods of authentication available which must be enabled in the pg_hba.conf file on the AlloyDB server.

   Find instructions about authentication setup on the AlloyDB Server here.

   Authenticating with MD5 Authentication

   This authentication method must be enabled by setting the auth-method in the pg_hba.conf file to md5.

   Authenticating with SASL Authentication

   This authentication method must be enabled by setting the auth-method in the pg_hba.conf file to scram-sha-256.

   Authenticating with Kerberos

   The authentication with Kerberos is initiated by AlloyDB Server when the ∏ is trying to connect to it. You should set up Kerberos on the AlloyDB Server to activate this authentication method. Once you have Kerberos authentication set up on the AlloyDB Server, see the Kerberos section of the help documentation for details on how to authenticate with Kerberos.

   Below is a typical connection string:

   User=alloydb;Password=admin;Database=alloydb;Server=127.0.0.1;Port=5432

   👁 The required connection properties in the Entity Data Model Configuration Wizard. (JSON is shown.)
   

2. Select the desired tables and views and click Finish to create the data model.

   👁 The last step of the Entity Data Model Configuration Wizard, where tables are imported into the entity model.
   
3. Build the project. The generated files can be used to create the AlloyDB connection in LINQPad.

Connect to AlloyDB Data in LINQPad

After you have obtained the required connection properties and created the data model assembly, follow the steps below to start using the data model in LINQPad.

1. Open LINQPad and click Add Connection.

2. Select the "Use a typed data context from your own assembly" option.

3. Select Entity Framework DbContext.

   👁 The Choose Data Context dialog.
   

4. Click Browse next to the Path to Custom Assembly box and browse to your project folder. Browse to the .dll or .exe under the bin folder.

5. Select the name of the DbContext.
6. If you saved your connection string in App.Config, specify the path to the App.config.

You can now query AlloyDB data through LINQPad. For examples of the supported LINQ queries, see the "LINQ and Entity Framework" chapter in the help documentation.