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From Michael Armbrust <mich...@databricks.com>
Subject Re: problem with reading source code-pull out nondeterministic expresssions
Date Wed, 30 Dec 2015 19:00:45 GMT
The goal here is to ensure that the non-deterministic value is evaluated
only once, so the result won't change for a given row (i.e. when sorting).

On Tue, Dec 29, 2015 at 10:57 PM, 汪洋 <tiandiwoxin@icloud.com> wrote:

> Hi fellas,
> I am new to spark and I have a newbie question. I am currently reading the
> source code in spark sql catalyst analyzer. I not quite understand the
> partial function in PullOutNondeterministric. What does it mean by "pull
> out”? Why do we have to do the "pulling out”?
> I would really appreciate it if somebody explain it to me.
> Thanks.
>

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