我一直在試圖限制這個查詢與多個作者(應該是四個)的書籍,但我無法弄清楚。有人可以幫忙嗎?如何將此查詢限制爲只有那些擁有多個作者的書籍?
這裏是我的代碼:
SELECT title, COUNT(authorid) AS "Number of Authors"
FROM book_author, books, publisher
WHERE publisher.pubid(+) = books.pubid
AND books.bookid(+) = book_author.bookid
GROUP BY title;
下面是結果:
SQL> SELECT title, COUNT(authorid) AS "Number of Authors"
2 FROM book_author, books, publisher
3 WHERE publisher.pubid(+) = books.pubid
4 AND books.bookid(+) = book_author.bookid
5 GROUP BY title;
TITLE Number of Authors
------------------------------ -----------------
DATABASE IMPLEMENTATION 3
PAINLESS CHILD-REARING 3
HOW TO GET FASTER PIZZA 1
SHORTEST POEMS 1
BIG BEAR AND LITTLE DOVE 1
BODYBUILD IN 10 MINUTES A DAY 2
HOLY GRAIL OF ORACLE 1
HANDCRANKED COMPUTERS 2
HOW TO MANAGE THE MANAGER 1
COOKING WITH MUSHROOMS 1
BUILDING A CAR WITH TOOTHPICKS 1
E-BUSINESS THE EASY WAY 1
REVENGE OF MICKEY 1
THE WOK WAY TO COOK 1
14 rows selected.
任何幫助將非常感激。
你是想限制你的結果,具有比一個作家更多的書?或者寫了多本書的作者?你在問作者是否寫過多本書。但是,您的查詢只能合理地限於擁有多個作者的圖書。 –
對,我用錯了。 – NewtonEntropy