Question

I am trying to write a query to get a report that shows which book has been loaned out the most. I have a query to get the actual book loaned out most, but I need to be able to show the title of that book, which is in another table.

SELECT * FROM LOAN;

LOANID     BOOKID     CUSTID OUTDATE   INDATE    DUEDATE

SELECT * FROM BOOK;

AUTHORID     BOOKID   BKISBN   BKSTATUS   BKTITLE  BKSERIES  BKTYPE   BKNUMBER

The following query is what I have so far and is getting the 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;

RESULT:

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

Now I need BkTitle from the Book Table.

Can anyone assist?

Answer 1

Try

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