objects. Each command has a particular function … a command object to perform a selection of the data from the original data source (so that the data can be stored for processing in the dataset), and command objects to add, edit and delete rows back to the original data source. It performs these operations using the diffgrams that were mentioned when discussing the dataset. Think of the DataAdapter as the conduit between the original data source (such as a database, file, etc.) and the in-memory representation of the data for use in your application (the dataset).
There are many others, however this should get you started.
By the way, with the exception of the DataSet, specific versions of the Connection, Command, DataReader and DataAdapters are provided for each specific type of data source you choose to use. So, for example, there is the SqlConnection, the SqlCommand, the SqlDataReader and the SqlDataAdapter, which are part of the System.Data.SqlClient namespace. Why do this? To optimize these objects and specialize them for the peculiarities that make each data source different.
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