public static List <ChunkHashModel> GetChunksByFileId(int fileId)
        {
            List <ChunkHashModel> list = new List <ChunkHashModel>();
            string        sqlQuery     = "SELECT * FROM chunk WHERE chunk.file_id=" + fileId;
            SqlDataReader dr           = Database.Instance.GetDataReader(sqlQuery);

            while (dr.Read())
            {
                ChunkHashModel chunk = new ChunkHashModel(dr);
                list.Add(chunk);
            }
            dr.Close();
            return(list);
        }
        public static byte[] GetChunkByChunkIdAndFileId(int chunkId, int fileId)
        {
            List <ChunkHashModel> list = new List <ChunkHashModel>();
            string        sqlQuery     = "SELECT * FROM chunk WHERE chunk.file_id=" + fileId + " AND chunk.chunk_id=" + chunkId;
            SqlDataReader dr           = Database.Instance.GetDataReader(sqlQuery);

            if (dr.Read())
            {
                ChunkHashModel chunk = new ChunkHashModel(dr);
                dr.Close();
                return(chunk.hash);
            }
            else
            {
                dr.Close();
                return(null);
            }
        }