Visual Basic® .NET Power Coding

Using the DataReader Class

The DataSet class is a central figure in ADO.NET. However, you have other options for reading data. Suppose, for example, you only want to iterate through a set of data, perhaps browsing. You don't need to scroll back and forth, and you don't need to update the data. You have the option of using a DataReader object for read-only and forward-only data. The DataReader class yields better performance heuristics than the DataSet class for forward-only browsing. The technique for using a DataReader is similar to that for initializing a DataSet.

The DataReader is requested from a command object. We still need a connection, but we don't need an adapter or a DataSet. Listing 11.4 demonstrates how to initialize a command and ...