Querying with the DataReader
The CData ADO.NET Provider for Blackbaud Raisers Edge NXT implements two ADO.NET interfaces you can use to retrieve data from BlackBaud Raiser's Edge NXT: RaiserEdgeNXTDataAdapter and RaiserEdgeNXTDataReader objects. Whereas RaiserEdgeNXTDataAdapter objects retrieve a single result set of all the data that matches a query, RaiserEdgeNXTDataReader objects fetch data in subset increments as needed.
Using the RaiserEdgeNXTDataReader
The RaiserEdgeNXTDataReader retrieves data faster than the RaiserEdgeNXTDataAdapter because it can retrieve data in pages. As you read data from the RaiserEdgeNXTDataReader, 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 Constituents table:
C#
string connectionString = "InitiateOAuth=GETANDREFRESH;SubscriptionKey=MySubscriptionKey;OAuthClientId=MyOAuthClientId;OAuthClientSecret=MyOAuthClientSecret;CallbackURL=http://localhost:33333;"; using (RaiserEdgeNXTConnection connection = new RaiserEdgeNXTConnection(connectionString)) { RaiserEdgeNXTCommand cmd = new RaiserEdgeNXTCommand("SELECT * FROM Constituents", connection); RaiserEdgeNXTDataReader rdr = cmd.ExecuteReader(); while (rdr.Read()) { Console.WriteLine(String.Format("\t{0} --> \t\t{1}", rdr["Id"], rdr["AddressLines"])); } }
VB.NET
Dim connectionString As String = "InitiateOAuth=GETANDREFRESH;SubscriptionKey=MySubscriptionKey;OAuthClientId=MyOAuthClientId;OAuthClientSecret=MyOAuthClientSecret;CallbackURL=http://localhost:33333;" Using connection As New RaiserEdgeNXTConnection(connectionString) Dim cmd As New RaiserEdgeNXTCommand("SELECT * FROM Constituents", connection) Dim rdr As RaiserEdgeNXTDataReader = cmd.ExecuteReader() While rdr.Read() Console.WriteLine([String].Format(vbTab & "{0} --> " & vbTab & vbTab & "{1}", rdr("Id"), rdr("AddressLines"))) End While End Using