ADO.NET Provider for Apache HBase

Build 21.0.7930

Querying with the DataAdapter

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

Using the ApacheHBaseDataAdapter

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 ApacheHBaseDataAdapter is slower than the ApacheHBaseDataReader 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 Account table:

C#

string connectionString = "Server=127.0.0.1;Port=8080;";

using (ApacheHBaseConnection connection = new ApacheHBaseConnection(connectionString)) {
  ApacheHBaseDataAdapter dataAdapter = new ApacheHBaseDataAdapter(
  "SELECT Id, Name FROM Account", connection);

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

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

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

VB.NET

Dim connectionString As String = "Server=127.0.0.1;Port=8080;"

Using connection As New ApacheHBaseConnection(connectionString)
  Dim dataAdapter As New ApacheHBaseDataAdapter("SELECT Id, Name FROM Account", connection)

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

  Console.WriteLine("Contents of Account.")

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

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Build 21.0.7930