As you know, NaN is a “Not a Number”.
How do you think, what would be the result of the following query? (0f/0 == NaN)
select count(*) cnt from dual where rownum < 0f/0;
Answer
SQL> select count(*) cnt, 0f/0 from dual where rownum < 0f/0;
CNT 0F/0
---------- ----------
1 Nan
1 row selected.
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Ok, when you know the result, try to guess what will return this query:
select count(*) cnt from dual where 1f/0 < 0f/0;
Answer
SQL> select count(*) cnt from dual where 1f/0 < 0f/0;
CNT
----------
1
1 row selected.
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PS
1 * X < 0 * Y
So we know now which non-negative values we should to substitute for X and Y in this expression, to make it true.
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