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mysql – SQL – 理解’JOIN’语法,顺序

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我的任务之一是将访问SQL转换为Oracle SQL.
我在MS访问中运行查询,这是关系表,查询SQL和查询结果：

访问查询SQL

SELECT PUBLISHER.PUBLISHER_CODE, PUBLISHER.PUBLISHER_NAME, BOOK.TITLE, BOOK.TYPE, INVENTORY.BRANCH_NUM, BRANCH.BRANCH_NAME
FROM PUBLISHER INNER JOIN (BRANCH INNER JOIN (BOOK INNER JOIN INVENTORY ON BOOK.BOOK_CODE = INVENTORY.BOOK_CODE) ON BRANCH.BRANCH_NUM = INVENTORY.BRANCH_NUM) ON PUBLISHER.PUBLISHER_CODE = BOOK.PUBLISHER_CODE
WHERE (((BOOK.TYPE)='FIC') AND ((BRANCH.BRANCH_NAME)='Henry on the Hill'))
ORDER BY PUBLISHER.PUBLISHER_NAME;

考虑到MS SQL可能在oracle中工作,我尝试了它：

SQL> SELECT PUBLISHER.PUBLISHER_CODE, PUBLISHER.PUBLISHER_NAME, BOOK.TITLE, BOOK.TYPE, INVENTORY.BRANCH_NUM, BRANCH.BRANCH_NAME
  2  FROM PUBLISHER INNER JOIN (BRANCH INNER JOIN (BOOK INNER JOIN INVENTORY ON BOOK.BOOK_CODE = INVENTORY.BOOK_CODE) ON BRANCH.BRANCH_NUM = INVENTORY.BRANCH_NUM) ON PUBLISHER.PUBLISHER_CODE = BOOK.PUBLISHER_CODE
  3  WHERE (((BOOK.TYPE)='FIC') AND ((BRANCH.BRANCH_NAME)='Henry on the Hill'))
  4  ORDER BY PUBLISHER.PUBLISHER_NAME;

no rows selected

显然这没有用.
所以,我有点切入/粘贴/编辑我的oracle 11g.这是我得到的：

SQL> SELECT PUBLISHER.PUBLISHER_CODE, PUBLISHER.PUBLISHER_NAME, BOOK.TITLE, BOOK.TYPE,
  2   INVENTORY.BRANCH_NUM, BRANCH.BRANCH_NAME
  3  FROM PUBLISHER
  4   inner join BOOK  ON PUBLISHER.PUBLISHER_CODE = BOOK.PUBLISHER_CODE
  5  inner join INVENTORY on INVENTORY.BRANCH_NUM = BRANCH.BRANCH_NUM
  6  inner join BRANCH on INVENTORY.BRANCH_NUM = BRANCH.BRANCH_NUM
  7   where BOOK.BOOK_TYPE = 'FIC'
  8   and BRANCH.BRANCH_NAME = 'Henry on the Hill';
inner join INVENTORY on INVENTORY.BRANCH_NUM = BRANCH.BRANCH_NUM
                                               *
ERROR at line 5:
ORA-00904: "BRANCH"."BRANCH_NUM": invalid identifier

为什么我得到这个：
   第5行的错误：
    ORA-00904：“BRANCH”.“BRANCH_NUM”：标识符无效

连接的顺序是否会影响任何事情？
正如你所看到的,我确实从一个表到另一个表.

语法顺序有问题吗？ EX：

INVENTORY.BRANCH_NUM = BRANCH.BRANCH_NUM上的内连接BRANCH
要么
BRANCH.BRANCH_NUM = INVENTORY.BRANCH_NUM上的内连接BRANCH

那有关系吗？

Oracle SQL中的连接是否按正确的顺序正确格式化？

如果是这样,为什么不运行？

旁注,这是一个在线课程,虽然讲师非常专注,但我在这里学到了很多东西,从阅读其他帖子,并提出自己的问题.谢谢大家！

解决方法:

您的原始查询加入了INVENTORY,如下所示：

inner join INVENTORY ON BOOK.BOOK_CODE = INVENTORY.BOOK_CODE

试试这个：

select PUBLISHER.PUBLISHER_CODE, PUBLISHER.PUBLISHER_NAME, BOOK.TITLE, BOOK.TYPE, INVENTORY.BRANCH_NUM, BRANCH.BRANCH_NAME
from PUBLISHER
inner join BOOK on PUBLISHER.PUBLISHER_CODE = BOOK.PUBLISHER_CODE
inner join INVENTORY on BOOK.BOOK_CODE = INVENTORY.BOOK_CODE
inner join BRANCH on BRANCH.BRANCH_NUM = INVENTORY.BRANCH_NUM
where BOOK.TYPE = 'FIC'
    and BRANCH.BRANCH_NAME = 'Henry on the Hill'
order by PUBLISHER.PUBLISHER_NAME;

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