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

Using the CDSDataReader

The CDSDataReader retrieves data faster than the CDSDataAdapter because it can retrieve data in pages. As you read data from the CDSDataReader, it periodically requests the next page of results from the data source, if required. This causes results to be returned at a faster rate. The following example selects all the columns from the Accounts table:

C#

string connectionString = "InitiateOAuth=GETANDREFRESH;OrganizationUrl=https://myaccount.crm.dynamics.com/;";

using (CDSConnection connection = new CDSConnection(connectionString)) {
  CDSCommand cmd = new CDSCommand("SELECT * FROM Accounts", connection);
  
  CDSDataReader rdr = cmd.ExecuteReader();

  while (rdr.Read()) {
    Console.WriteLine(String.Format("\t{0} --> \t\t{1}", rdr["accountid"], rdr["Name"]));
  }
}

VB.NET

Dim connectionString As String = "InitiateOAuth=GETANDREFRESH;OrganizationUrl=https://myaccount.crm.dynamics.com/;"

Using connection As New CDSConnection(connectionString)
  Dim cmd As New CDSCommand("SELECT * FROM Accounts", connection)

  Dim rdr As CDSDataReader = cmd.ExecuteReader()

  While rdr.Read()
    Console.WriteLine([String].Format(vbTab & "{0} --> " & vbTab & vbTab & "{1}", rdr("accountid"), rdr("Name")))
  End While
End Using