How can i create a webservice which is checking table for some periodically in database in asp.net?

Question

I wanted to checking my database table for periodically.So how can i create a webservice and how can i configure it.

Answer 1

basically what you need is, something which is always running and hence can make periodic calls.

There are a number of ways to do it

1. (Since ASP.NET hence) You can make a Windows Service, and host this service on your server, since server is always running, this Windows Service will make request to your webservice, update database or watever you want

2. You can use SQL Jobs to do it. You can call a webservice from a job, through a SSIS (Sql Server Integration Service) Package. These packages are very very robust in nature, they can do almost any db activity that you want them to do, including webservice request.

3. And finally, you can use third party tools such as Quartz.Net

References:

1. this is how you can call a webservice through a windows service.
2. this is how you can call a webservice through a ssis package.
3. this is how you can integrate a SSIS package in a SQL Job
4. this is how you can create a windows service
5. this is how you can create a SSIS package
6. this is how you can get answer/tutorial of almost anything

Example:

simplest of all of these would be a Windows Service. Making a windows service and hosting it on the machine(server) is very easy, use one of the given links (specially the last link). Usually, in Windows Service, you do some activity in OnStart event. you can place a timer inside this OnStart and upon TimerTick(), you can request your webservice.

something like this:

class Program : ServiceBase
    {
        System.Timers.Timer timer;

        static void Main(string[] args)
        {
            ServiceBase.Run(new Program());
        }
        public Program()
        {
            this.ServiceName = "My Service";
        }
        protected override void OnStart(string[] args)
        {
            base.OnStart(args);
            InitializeTimer();

        }

        protected override void OnStop()
        {
            base.OnStop();

            //TODO: clean up any variables and stop any threads
        }

        protected void InitializeTimer()
        {
            try
            {
                if (timer == null)
                {
                    timer = new System.Timers.Timer();
                    timer.Enabled = true;
                    timer.AutoReset = true;
                    timer.Interval = 60000 * 1;
                    timer.Enabled = true;
                    timer.Elapsed += timer_Elapsed;
                }

            }
            catch (Exception ex)
            {
                Utility.WriteLog("Exception InitialiseTimer : " + ex.Message.ToString());
            }
            finally
            {
            }
        }

        protected void timer_Elapsed(object source, System.Timers.ElapsedEventArgs e)
        {
                        
            TimerTick();
            timer.Interval = 60000 * Convert.ToDouble(ConfigurationManager.AppSettings["TimerInerval"]);
        }

        private void TimerTick()
        {
            try
            {
                DownloadFromFTPandValidate objDownLoadandValidate = new DownloadFromFTPandValidate();
                objDownLoadandValidate.ProcessMain();
            }
            catch (Exception ex)
            {
                Utility.WriteLog("Exception InitialiseTimer : " + ex.Message.ToString());
            }
        }
    }

Here, class DownloadFromFTPandValidate wraps the code to db activity. It shd give you an idea.

Answer 2

You will need a job scheduler for periodical task. I recommend you a good one. Check out this link: http://quartznet.sourceforge.net/

Answer 3

Why not using a trigger on your table which runs a stored procedure once data was modified, then use the xp_cmdshell to access the commandline form your stored procedure so you can run for example a batch file or whatever.