如何在oracle中限制返回结果集的大小
Oracle不支持类似于 MySQL 中的 limit. 但你还是可以rownum来限制返回的结果集的行数.
如果你只希望返回前十行纪录，你可以这样写：
SELECT * FROM table WHERE ROWNUM但是下面的语句是不对的：
SELECT * FROM table WHERE ROWNUM>90 AND ROWNUM这是因为 Oracle 认为这个条件不成立，所以没有返回。
你应该这样写：
SELECT * FROM table WHERE ROWNUMminus
SELECT * FROM table WHERE ROWNUM
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