Ado.net consists of classes that allow a .NET application to connect to the data source, executes commands and manage disconnected data. One of the key Differences between ADO.NET and other database technologies is how it deals with Challenge with different data sources, that means, the code you use to connect to an SQL Database will not differ that much to the one connecting to an Oracle Database. In many previous database technologies like ADO, a programmer had to use generic set of objects, no matter what the underlying data source is. That means if you have a Data layer, your Dal(Data Access Layer) Class can be used on Both Oracle and SQL, so there is nothing to change, but now in .NET it’s a Different Story, Ado.net uses provider model, that means I cannot connect to a SQL database with a OleDb Provider or Oracle Provider. What are providers? Data Providers as a set of ADO.NET Classes that allows you to access certain databases execute commands, retrieve data and more. So that means in order to connect to the SQL database you need to have a Provider of “SQltype” SQLClient. The Data Provider is a Middle man or a Bridge between your Database and your Application. The Data Provider is made up of the Following Classes.
Connection – we use this to establish a connection to the Data Source, that’s where you will pass your constructor with a connection string.
Command - We use the command object to execute the commands and storedprocedures.
Datareader - A datareader is a read only, forward only access to the data retrieved from a query and its normally used on read only data, or to Populate Comboboxes and more.
DataAdapter - This object performs two tasks, we use it to fill the Dataset (Disconnected Recordsets as I call it, but this one is powerful it carries a tables, that means a Dataset can contain many tables.)And another thing you can do with the adapter is to make changes to the Data, by first Connecting to the Datasource and making Changes.
Each Data provider has a specific implementation of Connection, Command and Adapter. That means if you need to a SQl database, you should use SQLConnection Class.
My Advice to those who are not yet in .NET is that, you buy a Book in .NET. well I have some Good Books you can get from Apress by Matthew MacDonald and Mario Szpuszta. Get some online training at www.itfunda.com. But for now its time for you to rush to a Book store and move to .NET
That was short J