How to get meaningful values from json object and to work with them

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C#

JSON

Hi, everyone. I work with json object in my c# application. I deserialized the json successfully and what I want is to take only meaningful properties (properties with actual values) from the json and to use them (actually I have to update database tables using these properties).

What I have tried:

For example let's see "TicketsData" class. Here it is:

public class TicketsData
    {
        public int id { get; set; }
        public string ticket_number { get; set; }
        public int user_id { get; set; }
        public int? origin_id { get; set; }
        public int priority_id { get; set; }
        public int sla_plan_id { get; set; }
        public int status_id { get; set; }
        public int? timezone_id { get; set; }
        public string is_auto_assigned { get; set; }
        public string created_at { get; set; }
        public string updated_at { get; set; }
        public int? created_by { get; set; }
        public string closed_at { get; set; }
        public string subject { get; set; }
        public string first_assigned_agent_or_team { get; set; }
        public string last_assigned_agent_or_team { get; set; }
        public string service_fulfill { get; set; }
        public int? no_of_workflow_positions { get; set; }
        public double? invoice_amount { get; set; }
        public object invoiceDetails { get; set; }
    }

Part of the json dealing with "TicketsData":

ticketsData
5
updated_at "2018-09-20 14:21:40"
29 {…}

I use reflection in my code:

public void UpdateEntriesFrom_tbl_ts_TicketsData(Dictionary<int, TicketsData> ticketsData)
        {
            foreach (KeyValuePair<int, TicketsData> entry in ticketsData)
            {
                Type t = entry.Value.GetType();
                PropertyInfo[] props = t.GetProperties();
                Dictionary<string, object> dict = new Dictionary<string, object>();
                foreach (PropertyInfo prp in props)
                {
                    object value = prp.GetValue(entry.Value, new object[] { });
                    dict.Add(prp.Name, value);
                }

                foreach (var item in dict)
                {
                        if (item.Value != null)
                        {                                                       
                        UpdateEntry("tbl_ts_TicketsData", item.Key, item.Value,
entry.Key);
                        }   
                }
            }
}

The problems I am facing are two. First problem is that the reflection gets all properties of "TicketsData" class including the "id" and what I need is all properties without "id". The second problem is that if I use the above code, I make a check:

if (item.Value != null)
{ 
UpdateEntry("tbl_ts_TicketsData", item.Key, item.Value,
entry.Key);
}

but in my db table "tbl_ts_TicketsData" there are fields like "user_id" which are (int, not null) and when json is as the above snippet, "user_id" comes with default value of "0", passes the check

if (item.Value != null)

and triggers the update method, which is not what I want (I want to use only the meaningful fields from the json). I tried another approach without reflection like this:

foreach (KeyValuePair<int, TicketsData> entry in ticketsData)
{
         if (entry.Value.user_id != 0)
         {
                    UpdateEntry("tbl_ts_TicketsData", "user_id", entry.Value.user_id, entry.Key);
         }
}

but the problem with that approach is thah "0" is a valid digit for "id" column of "User" table and I can miss a case if I use the code above.
Can you help me to get only the meaningful properties (properties with real not defalut values) from the deserialized json so I to be able to use them?