Tocomplete this task, the DataAdapter requires two pieces of information,or parameters: The primary function of a DataAdapter is to retrieve data from adata store and push it into a DataTable in the DataSet. Figure 3.4 illustrates the DataAdapter Object Model.
Like the other objects in the Managed Providers, the DataAdapter comes in two stock flavors, the SqlDataAdapter and the OleDbDataAdapter. The DataAdapter is made up of four command methods, a TableMappings collection, a Command collection, and an Exception collection (for OleDbErrors). Unlike the past model of connection-based data processing, the DataAdapter works on a disconnected message-based model, revolving around and delivering chunks of information in a disconnected fashion. You used the DataTables in the DataSet to populate one or more server controls on an ASP.NET Web Form.The DataAdapter is the bridge between the DataSet andthe data store. In Chapter 2, you looked at the DataSet as a collection of DataTable objects. Programming Data-Driven Web Applications with ASP.NET
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