How to Code a Windows Service that Updates the Database Table Nightly

Question: How do you write C-Sharp Code that runs as a Windows Background Service to update the Database Table nightly?

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Answer: If you want an Application Service to run in a Background, there are many ways to do it, depending on your scenario. If you have an Entity Framework Context Class (Data Layer) then you just need to Inject that Context Class in the Dependency Container and then retrieve it in the Service Repository Class.

However, if you just want a very simple Windows Service that does not require Dependency Injection, then take a look at the code below. Here's an example of a Windows service that updates a database table nightly using C# and the .NET Framework:

using System;
using System.ServiceProcess;
using System.Timers;
using System.Data.SqlClient;

namespace MyDatabaseUpdaterService
    public partial class DatabaseUpdaterService : ServiceBase
        private Timer _timer;

        public DatabaseUpdaterService()

        protected override void OnStart(string[] args)
            // Set up the timer to run every night at 2:00 AM
            _timer = new Timer();
            _timer.Interval = TimeSpan.FromHours(24).TotalMilliseconds;
            _timer.Elapsed += new ElapsedEventHandler(OnTimerElapsed);
            DateTime now = DateTime.Now;
            DateTime nextRun = new DateTime(now.Year, now.Month, now.Day, 2, 0, 0).AddDays(1);

        protected override void OnStop()
            // Stop the timer when the service is stopped

        private void OnTimerElapsed(object sender, ElapsedEventArgs e)
            // Connect to the database and update the table
            string connectionString = "Data Source=myServerAddress;Initial Catalog=myDataBase;User ID=myUsername;Password=myPassword;";
            string updateQuery = "UPDATE MyTable SET MyColumn = MyNewValue WHERE MyCondition = true;";
            using (SqlConnection connection = new SqlConnection(connectionString))
                using (SqlCommand command = new SqlCommand(updateQuery, connection))

To use this code, you'll need to create a new #Windows #Service project in #Visual #Studio and add this code to the Service1.cs file. You'll also need to add a reference to the System.Data.SqlClient assembly, and modify the connectionString and updateQuery variables to match your database configuration and table update logic.

Once you've built and installed the service, you can start it from the Services control panel in Windows. The service will run automatically every night at 2:00 AM, and update the database table with the specified logic.

[Note]: If at all, you should avoid including Timers in the #Main #Application where there are Hot Paths, this would create a deadlock in Threading and might create #Thread #Pool Stavation. The code above is just a simple and dirty way to create a Windows Service that accomplishes the task. For Production Ready Code, look into creating Dependency Injection and using an ORM such as Entity Framework to manage your Data Access Layer.

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