Re: LNNVL function

Jonathan Lewis wrote:

>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
>
> The educated person is not the person
> who can answer the questions, but the
> person who can question the answers -- T. Schick Jr
>
>
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>
>The Co-operative Oracle Users' FAQ
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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?
>>
>>

Thanks. But this still leaves open a question. Where is it hidden? It isn't a stand-alone object.
It isn't in a package? It isn't in any source code in \rdbms\admin. The only place I can find any
reference to it is inside oracle.exe.

Thanks.

-- 
Daniel Morgan
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