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

Using the ApachePhoenixDataAdapter

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 ApachePhoenixDataAdapter is slower than the ApachePhoenixDataReader because the Fill method needs to retrieve all data from the data source before returning.

The following example selects the Id and Name columns of the SampleTable_1 table:

C#

string connectionString = "URL=http://localhost:8765;";

using (ApachePhoenixConnection connection = new ApachePhoenixConnection(connectionString)) {
  ApachePhoenixDataAdapter dataAdapter = new ApachePhoenixDataAdapter(
  "SELECT Id, Name FROM [SampleCatalog_1].[SampleSchema_1].SampleTable_1", connection);

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

  Console.WriteLine("Contents of SampleTable_1.");

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

VB.NET

Dim connectionString As String = "URL=http://localhost:8765;"

Using connection As New ApachePhoenixConnection(connectionString)
  Dim dataAdapter As New ApachePhoenixDataAdapter("SELECT Id, Name FROM [SampleCatalog_1].[SampleSchema_1].SampleTable_1", connection)

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

  Console.WriteLine("Contents of SampleTable_1.")

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