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From Dmitriy Lyubimov <dlie...@gmail.com>
Subject Re: H2O integration - intermediate progress update
Date Thu, 19 Jun 2014 01:19:09 GMT
E.g. i know for sure A %.% B is legal where A is string-keyed and b is
int-keyed.

This is kind of not the point. the point is that you can easily modify
rewriting rules and operators to cover misses. (there shouldn't be many,
since we've already written quite a bit of expressions out there).


On Wed, Jun 18, 2014 at 6:15 PM, Dmitriy Lyubimov <dlieu.7@gmail.com> wrote:

> I am not sure. There are more rewriting rules than i can remember, and i
> did not write an algorithm ( i think) that would involve this combination.
> I guess the best thing is to try in a shell or a unit test. if it falls
> thru, perhaps a new plan element needs to be added (although I am not very
> sure there isn't already). I know that there are join-based multiplicative
> operators there.
>
>
> On Wed, Jun 18, 2014 at 6:11 PM, Ted Dunning <ted.dunning@gmail.com>
> wrote:
>
>> On Wed, Jun 18, 2014 at 6:07 PM, Dmitriy Lyubimov <dlieu.7@gmail.com>
>> wrote:
>>
>> > in simple terms, if non-integer row keying is used anywhere, it tries to
>> > rewrite pipelines so that product orientations never require non-int
>> keys
>> > to denote columns. In case pipeline makes it impossible, optimizer will
>> > refuse to produce a plan.
>> >
>> > e.g. suppose A is distributed string-keyed.
>> >
>> > (A.t %.% A) collect  // ok
>> >
>>
>> What happens with the important case of  B.t %.% A where both A and B are
>> string keyed?
>>
>
>

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