Retrieving Data from an Analytical Data Source

Once you make a connection and create the query, you can retrieve any data. In ADOMD.NET, you can retrieve data using three different objects (CellSet, AdomdDataReader, and XmlReader) by calling one of the Execute methods of the AdomdCommand object.

Each of these three objects balances interactivity and overhead:

• Interactivity refers to the ease-of-use and amount of information available through the object model.

• Overhead refers to the amount of traffic that an object model generates over the network connection to the server, the amount of memory needed for the object model, and the speed with which the object model retrieves data.

To help you select the data retrieval object that best suits the needs of your application, the following table highlights the differences between interactivity and overhead for each object.

Object	Interactivity	Overhead	Retains dimensionality	Usage Information
CellSet	Highest	Moderately high, which results in slowest retrieval of data	Yes	Retrieving Data Using the CellSet
AdomdDataAdapter	Moderate	Moderate	No	Populating a DataSet from a DataAdapter
AdomdDataReader	Moderate	Moderate	No	Retrieving Data Using the AdomdDataReader
XmlReader	Lowest	Lowest, which results in fastest data retrieval	Yes	Retrieving Data Using the XmlReader