Issue with generics in c#
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I have a problem while adding a new class in my existing structure. I am going to explain my problem as much clear as i can:


    public interface Imust
    {
        string Name { get; set; }
        string File { get; set; }
        string RowKey { get; set; }
        string Time { get; set; }
        string PartitionKey { get; set; }
    }

    public class TA : TableServiceEntity, Imust
    {
        public string Time { get; set; }
        public string Name { get; set; }
        public string File { get; set; }
    }

    public class TB : TableServiceEntity, Imust
    {
        public string Time { get; set; }
        public string Name { get; set; }
        public string File { get; set; }
    }

    public class TC : TableServiceEntity, Imust
    {
        public string Time { get; set; }
        public string Name { get; set; }
        public string File { get; set; }
    }    

    public class _Table <T> : _Account where T : Imust 
    {
    }

Here the above 3 classes are implemented as Tables and its properties as its columns in my project. Imust interface is implemented in each class because in generic class i put an interface constraint. TableServiceEntity class contains the implementation for RowKey and PartitionKey.And this class is also inherited in all 3 entities.

**Problem** : Now i have to add a new table in my application. So for this i have to add a new class here which is 


    public class TD : TableServiceEntity
    {

    }    
I do not want this class to implement the Imust interface because it does not contain these columns. But  i have to pass it as a parameter in generic class `_Table`.Because this new class has different columns but it perform same function which other 3 entities does. Now how will i add this new class while maintaining my existing structur ? 

Please suggest me any better solution for this problem ?