SQL查詢 - 需要從不同的表中獲取信息

Question

我想寫一個查詢來獲得一個報告，顯示哪本書已經被借出最多。我有一個查詢來獲取最實際的圖書，但我需要能夠顯示該書的標題，該書位於另一個表中。

SELECT * FROM LOAN; 

LOANID  BOOKID  CUSTID OUTDATE INDATE DUEDATE 

SELECT * FROM BOOK; 

AUTHORID  BOOKID BKISBN BKSTATUS BKTITLE BKSERIES BKTYPE BKNUMBER 

下面的查詢是我迄今爲止，並得到BOOKID：

SELECT Q1.* FROM 
(SELECT BOOKID, COUNT(*) 
    AS BOOK_COUNT 
    FROM LOAN 
    GROUP BY LOAN.BOOKID) Q1, 
(SELECT MAX(Q2.BOOK_COUNT) 
    AS HIGH_COUNT 
    FROM (SELECT BOOKID, COUNT(*) 
    AS BOOK_COUNT 
    FROM LOAN 
    GROUP BY LOAN.BOOKID) Q2) Q3 
WHERE Q1.BOOK_COUNT = Q3.HIGH_COUNT; 

結果：

BOOKID BOOK_COUNT 
---------- ---------- 
     387   3 

現在我需要BkTitle從書籍表。

任何人都可以協助嗎？

Answer 1

嘗試

select b.bookid, b.BKTITLE , count(l.loanid) as cnt_loan 
from book b 
inner join loan l on l.bookid = b.bookid 
WHERE ROWNUM < 2 
group by b.bookid 
order by cnt_loan desc