First off, there are 5 columns in your table, but you list 6 values to return...
When I run a similar query on my DB, I get the same order of magnitude responsefor each for a total of 28767 rows for each query.
Stopwatch s1 = new Stopwatch();
Stopwatch s2 = new Stopwatch();
using (SqlConnection con = new SqlConnection(strConnect))
{
con.Open();
SqlCommand cmd1 = new SqlCommand("SELECT ID, UserID, EnterDate, Total, AU1, AU2, DE, ED, EN, OR, PA FROM dbo.MyTable", con);
using (SqlDataAdapter da = new SqlDataAdapter(cmd1))
{
DataTable dt = new DataTable();
s1.Start();
da.Fill(dt);
s1.Stop();
}
SqlCommand cmd2 = new SqlCommand("SELECT * FROM dbo.MyTable", con);
using (SqlDataAdapter da = new SqlDataAdapter(cmd2))
{
DataTable dt = new DataTable();
s2.Start();
da.Fill(dt);
s2.Stop();
}
}
Console.WriteLine("{0}:{1}", s1.ElapsedTicks, s2.ElapsedTicks);
The values I get for successive runs are:
5105014:2635936
3679955:6183447
5110977:4361559
4260305:3936449
So...I'd look closely at exactly how you are fetching the rows, and how you are timing it.