What is use of Command Builder in ASP.NET?

Command 开发者_如何学Gobuilder builds Parameter Object. What does it mean by parameter object? Why are they created ?

Why does Derive Parameter method need extra round trip to Data store ?

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I have only used it one time (when I needed to import some data and I was too lazy to build out my Sql statements) - to automatically generate insert, update, and delete statements to reconcile changes made to a DataSet with the associated database.

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlcommandbuilder.aspx