ADO: ActiveX Data Objects

ADO.NET Features

As the name implies, ADO.NET is an extension built upon the existing, traditional ADO object model. While ADO.NET will be very familiar to an ADO developer, several new features have been added to facilitate use with disconnected data sources:

• ADO.NET focuses on disconnected data.

• ADO.NET allows strongly typed language.

• ADO.NET works with hierarchical and relational data through XML.

Each of these differences have their own benefits, as explained in the following sections.

Disconnected Data

ADO.NET allows you to create disconnected n-tier applications. This feature is probably the biggest draw of ADO.NET. Traditional ADO was designed to work with tightly coupled application tiers, where state is maintained. In the web development paradigm, state is nonexistent.

With ADO.NET, the DataSet object is populated with the entire data that is needed in your application, and then the connection is closed, even if you are going to work with this data for a long time. When the data needs to be persisted to the data source, another connection is created, and then the data is persisted.

In ADO, you must state explicitly that you want to work with a disconnected Recordset, which can be done only with RDS objects: with ADO.NET, this choice is the default.

Strongly Typed Language

ADO.NET provides for a strongly typed language, which allows you to access collection classes and data that are normally parameterized with the actual name. For instance, to display the first name of the current ...