将＃SQLite查询结果添加到List 时，C＃应用程序冻结

I have a query which returns 66 rows, each of these rows contains a unique_id and I want to save the results in a List so I can use them for further queries. But the code freezes at the line which is supposed to add the rows to the list. I can't find where my problem is! This is My code:I have a query which returns 66 rows, each of t