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

Using the CouchbaseDataReader

The CouchbaseDataReader retrieves data faster than the CouchbaseDataAdapter because it can retrieve data in pages. As you read data from the CouchbaseDataReader, 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 Customer table:

C#

string connectionString = "User='myusername';Password='mypassword';Server='http://couchbase40'";

using (CouchbaseConnection connection = new CouchbaseConnection(connectionString)) {
  CouchbaseCommand cmd = new CouchbaseCommand("SELECT * FROM Customer", connection);
  
  CouchbaseDataReader rdr = cmd.ExecuteReader();

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

VB.NET

Dim connectionString As String = "User='myusername';Password='mypassword';Server='http://couchbase40'"

Using connection As New CouchbaseConnection(connectionString)
  Dim cmd As New CouchbaseCommand("SELECT * FROM Customer", connection)

  Dim rdr As CouchbaseDataReader = cmd.ExecuteReader()

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