How to get all values in same variable from SQLite, Windows Phone 8

I have SQLite database in my windows phone 8. But I want to show total value of an integer database value.

 public int dbTrans { get; set; }

I save numbers into that value day by day. For example I want to show total value of dbTrans from 10 JULY to 20 JULY. How can I handle over it ? Thanks