ORACLE QUERY与ROWNUM

Question

I am expecting the value to be listed from 1 to 899 for the following query. But it returns only the value from 1 to 667. Can somebody help me to find the reason

select rownum from all_tables where rownum <900

Answer 1

你有少于899个表。

Answer 2

由于源表/视图中缺少行而导致的最简单的行生成器是：

select rownum from dual connect by level < 900;

Answer 3

try:

select level as rnum
from dual
connect by level < 900;

Answer 4

select rownum from all_objects where rownum <900