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

Using the IBMCloudSQLQueryDataReader

The IBMCloudSQLQueryDataReader retrieves data faster than the IBMCloudSQLQueryDataAdapter because it can retrieve data in pages. As you read data from the IBMCloudSQLQueryDataReader, 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 [CloudObjectStorage_1].[SampleBucket_1].Jobs table:

C#

string connectionString = "Api Key=MyAPIKey;";

using (IBMCloudSQLQueryConnection connection = new IBMCloudSQLQueryConnection(connectionString)) {
  IBMCloudSQLQueryCommand cmd = new IBMCloudSQLQueryCommand("SELECT * FROM [CloudObjectStorage_1].[SampleBucket_1].Jobs", connection);
  
  IBMCloudSQLQueryDataReader rdr = cmd.ExecuteReader();

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

VB.NET

Dim connectionString As String = "Api Key=MyAPIKey;"

Using connection As New IBMCloudSQLQueryConnection(connectionString)
  Dim cmd As New IBMCloudSQLQueryCommand("SELECT * FROM [CloudObjectStorage_1].[SampleBucket_1].Jobs", connection)

  Dim rdr As IBMCloudSQLQueryDataReader = cmd.ExecuteReader()

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