Chapter 21. The DataReader Class
represents a read-only, forward-only stream of data, which is ideal
for quickly retrieving query results. The
DataReader is useful if you don’t
need the full support for versioning and change tracking provided by
DataSet. Best of all, because the
DataReader loads only a single row into memory at
a time, it has a small in-memory footprint.
You can’t create a
directly. Instead, you must use the
method of a
Command object that returns a
DataReader. Chapter 5 presents
complete examples that show how to use the
DataReader in various scenarios.