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From Jinfeng Ni <jinfengn...@gmail.com>
Subject Re: are random numbers broken?
Date Tue, 12 Apr 2016 00:53:33 GMT
Sounds like there are two issues.

1.  random() delivers the same value when used multiple times in each
returned row. This seems to be caused by a bug in common subexpression
(CSE) reduction, which identify the two appearances of random() are
CSE. As a result, the generated code share the only instance of
random().

2. rand(). Looks like Drill does not recognize hive's rand() as
'isRandom'=true. As such, rand() is regarded as a constant expression
in generated code.

Both of them are bugs that we should fix.

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