The CData ADO.NET Provider for Teradata implements two ADO.NET interfaces you can use to retrieve data from Teradata: TeradataDataAdapter and TeradataDataReader objects. Whereas TeradataDataAdapter objects retrieve a single result set of all the data that matches a query, TeradataDataReader objects fetch data in subset increments as needed.

Using the TeradataDataAdapter

Use the adapter's Fill method to retrieve data from the data source. An empty DataTable instance is passed as an argument to the Fill method. When the method returns, the DataTable instance is populated with the queried data. Note that the TeradataDataAdapter is slower than the TeradataDataReader because the Fill method needs to retrieve all data from the data source before returning.

The following example selects the ProductId and ProductName columns of the NorthwindProducts table:

C#

string connectionString = "User=Admin;Password=test123;Database=Northwind;DataSource=127.0.0.1";

using (TeradataConnection connection = new TeradataConnection(connectionString)) {
  TeradataDataAdapter dataAdapter = new TeradataDataAdapter(
  "SELECT ProductId, ProductName FROM \"CData\".\"dbo\".NorthwindProducts", connection);

  DataTable table = new DataTable();
  dataAdapter.Fill(table);

  Console.WriteLine("Contents of NorthwindProducts.");

  foreach (DataRow row in table.Rows) {
    Console.WriteLine("{0}: {1}", row["ProductId"], row["ProductName"]);
  }
}

VB.NET

Dim connectionString As String = "User=Admin;Password=test123;Database=Northwind;DataSource=127.0.0.1"

Using connection As New TeradataConnection(connectionString)
  Dim dataAdapter As New TeradataDataAdapter("SELECT ProductId, ProductName FROM \"CData\".\"dbo\".NorthwindProducts", connection)

  Dim table As New DataTable()
  dataAdapter.Fill(table)

  Console.WriteLine("Contents of NorthwindProducts.")

  For Each row As DataRow In table.Rows
    Console.WriteLine("{0}: {1}", row("ProductId"), row("ProductName"))
  Next
End Using