Re: LNNVL function

As Richard pointed out,

      lnnvl(predicate) is true
if predicate is false or null.

I can't say "for sure", but I believe
it appeared somewhere around 7.3, or
maybe 7.2 to handle problems arising
from the SQL generated by a query co-ordinator for its parallel query slaves when Oracle was trying to get partition elimination on partition views.

(And if it really is there for PQ problems, I'd second Richard's advice - don't use it, you never know when it's going to disappear).

--
Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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"Rob Cowell" <rjc4687_at_hotmail.com> wrote in message
news:3FA1490E.C51D2C5_at_hotmail.com...


> Anyone got any ideas.

>

> SELECT 1 FROM DUAL

> WHERE LNNVL(1=2)

>

> returns

>

> 1

>

> Suggesting that LNNVL(1=2) evaluates to true

>

> But LNNVL(1=1) evaluates to false

>

> I assume there must be some NULL processing going on too because of

the


> function name.

>

> It seems totally undocumented and there's only one unhelpful mention

on


> Metalink.

>

> Anyone know for sure what it does?