Re: factorial

Could it be reduced to just

with factorial (n, f) as
( values(1, 1)
union all
select n+1, f*(n+1)
from factorial
where n<10
)

? Then, could the engine push the safety predicate (n<10) from outer query like this:

with factorial (n, f) as
( values(1, 1)
union all
select n+1, f*(n+1)
from factorial
)
select * from factorial where n<10

? (I guess not, as this is essentially my query:-(

If it cant push "n<10", then can it at least push "level<10":

with factorial (level, n, f) as
( values(1, 1, 1)
union all
select level+1, n+1, f*(n+1)
from factorial
)
select * from factorial where level<10;

?

In article <3C37DB75.6AC77849_at_yahoo.com>, Fan Ruo Xin says...
>
>
>try this:
>with factorial (level, n, f) as
> ( values(1, 1, 1)
> union all
> select level+1, n+1, f*(n+1)
> from factorial
> where level<10
> )
>select * from factorial;
>
>Just wonder why use sql to do this kind of thing?
>Regards,
>
>Fan Ruo Xin
>
>
>Mikito Harakiri wrote:
>
>> WITH
>> factorial AS (
>> select n+1, f*(n+1) from factorial
>> union
>> select 1, 1 from table(values(1,1)) )
>> SELECT f FROM factorial
>> WHERE n=5
>>
>> 1. Is this going to work?
>> 2. If not why, and what would be the correct recursive definition?
>
Received on Sun Jan 06 2002 - 06:46:57 CET