如何找到同一日期的重複記錄

Question

我有一個房間庫存表，每個房間每天有一個記錄， 但有些房間有一天的雙重記錄。我想查詢以提取這些ID。

Inventory_table => ID，roomid，inv_date ....

Answer 1

下面可能讓你與重複的房間列表。

select id, roomid, inv_date, count(room) 
from room_inventory 
group by id, roomid, inv_date 
having count(room) > 1; 

Answer 2

Select Id, count(*) from inventory_table group by roomid, inv_date having count(*)>1