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From Eric Owhadi <eric.owh...@esgyn.com>
Subject RE: question on normalization
Date Mon, 14 Dec 2015 21:31:38 GMT
Sorry should have said that "an" is not a key column. So any logic around
MDAM should not apply.
Eric

-----Original Message-----
From: Hans Zeller [mailto:hans.zeller@esgyn.com]
Sent: Monday, December 14, 2015 3:30 PM
To: dev <dev@trafodion.incubator.apache.org>
Subject: Re: question on normalization

Hi Eric, this is probably to get usable key predicates. "an <> 1" is not a
key range we could use, but "an < 1" and "an > 1" make two disjuncts for an
MDAM scan.

Hans

On Mon, Dec 14, 2015 at 1:25 PM, Eric Owhadi <eric.owhadi@esgyn.com> wrote:

> I am implementing predicate push down enhancement. doing so, I found
> something weird.
>
> If I do select an from t132 where an != 1
>
> The normalized predicate is ((an < 1) or <an >1))
>
> I would have expected a simple an <> 1
>
> There is probably a reason being this? But what is it?
>
> Thanks in advance for the help,
> Eric
>

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