protected void Application_Start(Object sender, EventArgs e)
{
System.Timers.Timer t=new System.Timers.Timer(1000*10);//每10秒触发一次
t.AutoReset=true;
t.Enabled=true;
t.Elapsed +=new System.Timers.ElapsedEventHandler(yourFun);
}

private void yourFun(object sender, System.Timers.ElapsedEventArgs e)
{
//这里是访问数据库的代码
}