查詢檢索過去24個月內租借最多的圖書

Question

如何查找過去24個月內租借最多的圖書？

rentedBooks (rentid, bookid, dateout, datein) 

我已經試過如下：

SELECT * FROM RENTEDBOOKS, COUNT(BOOKID) WHERE DATEIN >= DATEADD(MONTH, -24, GETDATE()); 

但一直收到錯誤提無效的標識符：S

注：我不使用MySQL的！

Answer 1

我不知道是怎麼回事你的WHERE子句（DATEADD，GETDATE），但其餘的應該是這個樣子......

SELECT BOOKID, COUNT(BOOKID) 
FROM RENTEDBOOKS 
WHERE ... 
GROUP BY BOOKID; 

Answer 2

SELECT BOOKID, COUNT(*) cnt 
FROM RENTEDBOOKS 
WHERE DATEIN >= sysdate - interval '24' month 
group by BOOKID 
order by cnt desc; 

編輯：

SELECT BOOKID, COUNT(*) cnt 
FROM RENTEDBOOKS 
WHERE DATEIN >= add_months(sysdate, -24) 
group by BOOKID 
order by cnt desc; 

Answer 3

WHERE DATEIN >= DATEADD('m',-24, Date$());