The initiative behind ADO.NET was to reimplement ADO using XML as a flexible and extensible format that is easily transmitted across networks like the Internet. We will talk more about XML and ADO.NET in Chapter 12.
The simple yet powerful revision to ADO in .NET is that the DataSet is disconnected. The benefit is that the client retrieves the data and can perform relevant operations without holding a connection to the database, returning to the database only when changes need to be posted. As you learned in this chapter, you can filter and sort data without requerying the database. You also learned that you have a variety of options, including using DataReader objects for faster forward and read-only data access, using the CommandBuilder class to generate SQL, building connection strings with the Data Link Properties wizard, and using application configuration files for storing and retrieving information like connection strings.
In the next chapter we will build on this information by looking at typed, object-oriented DataSet objects; XML serialization; stored procedures; database transactions; and a powerful programming technique that uses interfaces. Programming with ADO.NET interfaces will allow you to switch data providers ”databases ”without modifying your code.