ADO.NET DataSets
.

Thomas Wagner has some
interesting things to say about ADO.NET DataSets
. I
recall there was a long and drawn out discussion on the DM DOTNET
list about the performance of using DataReaders vs. DataSets, the
end result of which was that Microsoft’s admonishment to always use
DataSets is bullshit.
[
The .NET
Guy
]

Yes, this is a long running discussion, but I’m not convinced
that this supposed Microsoft policy stands up to much
scrutiny. I’ve been at an MSDN presentation at Microsoft’s UK base
where we were told, “…but if you want to get data out quickly,
don’t use a DataSet, always use a DataReader.”

Thomas
Wagner
says:

Over and
over and over I read that one ought to prefer a Dataset over a
Datareader because of the cost of opening and closing a db
connection when using a reader object. Can we make a mountain out
of a molehill to promote our latest achievements please?
Connections are pooled in most NET / SQL Server configs and
therefore are faster to open and close. Has anyone mentioned that
 fact whilst they
demote the  Datareader?
No!   Every other author espouses the party line
that you should cache datasets whenever feasible and eschew
Datareaders because of the cost of opening a connection. I can see
on a daily basis how developers confuse the concept of inheriting
datasets with traditional OO
programming.