Getting multiple records for same value in JSON

I've tried your code. Seems to be working as intended. It would seem that your problem lies with the data itself. Have you checked your logic for storing data? If there are duplicates in your data, naturally, duplicates will be retrieved.

Edit: I think there was a misunderstanding with the storing data part question. It's not how you store in the database I was asking, its how you were persisting the data. How do you persist your data or how the persistent data was stored? Was there any fetch logic before you arrived in this:

var mainDetails = kesc.tj_xhqd <--- This guy

The part where I tested your code:

class Program { static void Main(string[] args) { Random r = new Random(); List<Chingamajig> chinga = new List<Chingamajig>(); string[] verylongnum = new string[] { "00000000002312312", "34234002342342" }; int[] somenum = new int[] { 7, 14, 12, 28 }; for(int i = 0;i<100;i++) { Chingamajig c = new Chingamajig(); c.VeryLongNumbers = verylongnum[r.Next(0, 2)]; c.DateValue = DateTime.Now.AddMinutes((double)r.Next(-100, 101)); c.SomeNumber = somenum[r.Next(0, 4)]; chinga.Add(c); } foreach (Chingamajig c in chinga.OrderBy(x => x.VeryLongNumbers).ThenBy(y => y.DateValue).ThenBy(z => z.SomeNumber)) { Console.WriteLine("{0} : {1} : {2}", c.VeryLongNumbers, c.DateValue, c.SomeNumber); } var m = "00000000002312312"; var dt = DateTime.Now.Date; var interval = 2; var ee = chinga.Where(x => (x.VeryLongNumbers == m) && (x.DateValue >= dt)).AsEnumerable() .Select((z, i) => new { MSN = z.VeryLongNumbers, PingDT = z.DateValue, PingV = z.SomeNumber, i = i }) .Where(x => x.i % interval == 0).ToList(); Console.Clear(); foreach(var n in ee) { Console.WriteLine("{0} : {1} : {2} : {3}", n.MSN, n.PingDT, n.PingV, n.i); } Console.ReadLine(); } } public class Chingamajig { public string VeryLongNumbers { get; set; } public DateTime DateValue { get; set; } public int SomeNumber { get; set; } } 

So yeah.. I did test your code with mock data because your sample code had little meat in it.

Update: Try adding this to your code

var mainDetails = kesc.tj_xhqd //This line .AsNoTracking() .Where(m => (m.zdjh == msn) && (m.sjsj >= dt)) .AsEnumerable() .Select((x, i) => new { MSN = x.zdjh, PingDateTime = x.sjsj, PingValue = x.xhqd, i = i }) .Where(x => x.i % interval == 0) .ToList(); 

Not sure but this problem seems to be stemming from tables with no pkey. Not sure about your case though but below is a link for your reference Identical Rows