SqlConnection conn = new SqlConnection();
conn.ConnectionString = "Server=127.0.0.1;User ID=sa;Password=fdahgdrethj31313210212121;Database=northwind;Persist Security Info=True";
conn.Open();
SqlDataAdapter da = new SqlDataAdapter("select * from 表", conn);
SqlCommandBuilder thisBulder = new SqlCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds);
ds.WriteXml(@"C:\temp.xml");
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