# What is bigger than infinity?

Nan

``` select BINARY_DOUBLE_INFINITY INF, BINARY_DOUBLE_NAN NAN, greatest(BINARY_DOUBLE_INFINITY, BINARY_DOUBLE_NAN) GRE from t;```

``` ```

```INF NAN GRE --- --- --- Inf Nan Nan ```
Nan means not a number. It could be square root of -1, log of -1, 0/0, acos(1000), Inf-Inf, etc…

``` select SQRT(-1d), LN(-1d), 0/0d, acos(1000d), BINARY_DOUBLE_INFINITY-BINARY_DOUBLE_INFINITY from t; SQR LN- 00D ACO BIN --- --- --- --- --- Nan Nan Nan Nan Nan ```

According to the doc, it is greater than any value, inclusive positive infinity.

To check if a value is nan, it could be compared to BINARY_DOUBLE_NAN.
`where :z = BINARY_DOUBLE_NAN`
There is a function NANVL(:z, :y) which evaluates to :y when :z is equal Nan. if :z is not equal to Nan and :y is not null, then it evaluates to :z. NANVL evaluates to NULL when :z or :y is null.

``` select NANVL(1,null) from dual; NANVL ------ [null] ```

## 11 Replies to “What is bigger than infinity?”

1. neruup says:

You should ask Chuch Norris as he has counted to infinity, twice ðŸ™‚

2. but note than twice infinity is not bigger than infinity ðŸ™‚

select *
from dual
where binary_double_infinity*2
> binary_double_infinity;

No rows selected.

Anyway, I will ask him next time I see him on TV

3. “According to the doc, it [BINARY_DOUBLE_NAN] is greater than any value, inclusive positive infinity.”

it is not greater than itself:

SQL > select 1 from dual where BINARY_DOUBLE_NAN > BINARY_DOUBLE_NAN;

no rows selected

4. I can’t wait till Oracle will have implemented constants
Aleph-0, Aleph-1, …

Then, finally, continuum hypothesis will be trivially solved by
select 1 from dual where power(Aleph-0) = Aleph-omega

ðŸ˜€

5. I can’t wait till Oracle will have implemented constants
Aleph-0, Aleph-1, …

Then, finally, continuum hypothesis will be trivially solved by
select 1 from dual where power(Aleph-0) = Aleph-omega

6. I can’t wait till Oracle will have implemented constants
Aleph-0, Aleph-1, …
Then, finally, continuum hypothesis will be trivially solved by
select 1 from dual where power(Aleph-0) = Aleph-omega

7. and it is also not greater than BINARY_FLOAT_NAN and GREATEST(NULL,BINARY_DOUBLE_NAN) is NULL

8. I can’t wait until Oracle will have implemented the different infinite cardinals
Aleph-0, Aleph-1, …
Then, continuum hypothesis will be very elegantly decided by the query

select null
from dual
where power(2, ALEPH_0) = ALEPH_1

bets on the result are welcome

9. cfgauss says:

I can’t wait till Oracle will have implemented the different infinite cardinals
aleph-0, aleph-1, …

then, continuum hypothesis will very elegantly be decided by the query

select null
from dual
where power(2, ALEPH_0) = ALEPH_1