Dear, May be you need something like below code..
protected void UpdateData()
{
int intQuantity = 0;
SqlConnection con = new SqlConnection("Your Connectionstring here");
SqlCommand cmd = new SqlCommand("update product set quantity=@Quantity where productname=@Product", con); ;
cmd.CommandType = CommandType.Text;
cmd.Parameters.AddWithValue("@Quantity", intQuantity - 10);
cmd.Parameters.AddWithValue("@Product", "Sugar");
cmd.ExecuteNonQuery();
}
KiranKumar Roy
