/// <summary>
        /// Returns list of changes for single customer or all of the changes (all changes if custid = -1)
        /// </summary>
        public static List <changes> getChanges(SQLiteConnection sqlc2, int cust_id)
        {
            List <changes> lst = new List <changes>();

            string where = cust_id == -1 ? "" : " WHERE ugyfel_id=" + cust_id;

            string        command = "SELECT * FROM changelog";
            SQLiteCommand sqlk    = new SQLiteCommand(command, sqlc2);

            reader = sqlk.ExecuteReader();

            while (reader.Read())
            {
                changes c = new changes();

                c.id          = c_DBHandler.checkvalueInt(reader.GetInt32(reader.GetOrdinal("id")));
                c.cust_id     = c_DBHandler.checkvalueInt(reader.GetInt32(reader.GetOrdinal("ugyfel_id")));
                c.table       = c.before = c_DBHandler.checkvalueString(reader.GetInt32(reader.GetOrdinal("table")));
                c.before      = c_DBHandler.checkvalueString(reader.GetInt32(reader.GetOrdinal("before_change")));
                c.after       = c.before = c_DBHandler.checkvalueString(reader.GetInt32(reader.GetOrdinal("after_change")));
                c.whochanged  = c_DBHandler.checkvalueString(reader.GetInt32(reader.GetOrdinal("who_changed")));
                c.whenchanged = c_DBHandler.checkvalueString(reader.GetInt32(reader.GetOrdinal("when_changed")));

                lst.Add(c);
            }

            return(lst);
        }
        /// <summary>
        /// Returns the deleted customer list or a single deleted customer (list if custid = -1)
        /// </summary>
        public static List <changes> getDeletedCustomers(SQLiteConnection sqlc2, int custid)
        {
            List <changes> lst = new List <changes>();

            string where = custid == -1 ? "" : " WHERE ugyfel_id=" + custid;

            string        command = "SELECT * FROM deleted_customers" + where;
            SQLiteCommand sqlk    = new SQLiteCommand(command, sqlc2);

            reader = sqlk.ExecuteReader();

            while (reader.Read())
            {
                changes c = new changes();

                c.id          = c_DBHandler.checkvalueInt(reader.GetInt32(reader.GetOrdinal("id")));
                c.cust_id     = c_DBHandler.checkvalueInt(reader.GetValue(reader.GetOrdinal("ugyfel_id")));
                c.table       = "ugyfel";
                c.before      = c_DBHandler.checkvalueString(reader.GetValue(reader.GetOrdinal("customer_data")));
                c.after       = "";
                c.whochanged  = c_DBHandler.checkvalueString(reader.GetValue(reader.GetOrdinal("who_deleted")));
                c.whenchanged = c_DBHandler.checkvalueString(reader.GetValue(reader.GetOrdinal("when_deleted")));

                lst.Add(c);
            }

            return(lst);
        }