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

Using the VeevaVaultDataReader

The VeevaVaultDataReader retrieves data faster than the VeevaVaultDataAdapter because it can retrieve data in pages. As you read data from the VeevaVaultDataReader, 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 Documents table:

C#

string connectionString = "Url=myURL;User=myUser;Password=myPassword;";

using (VeevaVaultConnection connection = new VeevaVaultConnection(connectionString)) {
  VeevaVaultCommand cmd = new VeevaVaultCommand("SELECT * FROM Documents", connection);
  
  VeevaVaultDataReader rdr = cmd.ExecuteReader();

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

VB.NET

Dim connectionString As String = "Url=myURL;User=myUser;Password=myPassword;"

Using connection As New VeevaVaultConnection(connectionString)
  Dim cmd As New VeevaVaultCommand("SELECT * FROM Documents", connection)

  Dim rdr As VeevaVaultDataReader = cmd.ExecuteReader()

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