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From Josh Wills <jwi...@cloudera.com>
Subject Re: Joins and null values
Date Wed, 18 Feb 2015 22:43:05 GMT
Different from o.a.c.lib.Cartesian.cross(PCollection<U> left,
PCollection<T> right, int parallelism) in some way?

J

On Wed, Feb 18, 2015 at 2:41 PM, Bryan Baugher <bjbq4d@gmail.com> wrote:

>
> Maybe,
>
> PCollection<T>#join(PCollection<T>, JoinType) : PCollection<Pair<T,
T>>
>
> You could make additional methods for the different join strategies or
> maybe an enum perhaps?
>
> On Wed Feb 18 2015 at 3:58:38 PM Josh Wills <jwills@cloudera.com> wrote:
>
>> Hey Bryan,
>>
>> I like the idea of throwing exceptions when there are null values in one
>> of the collections in a join. Not sure if there are any other implications
>> of that I should think through first.
>>
>> On the convenience methods for PCollection joins, what do you have in
>> mind?
>>
>> J
>>
>>
>> On Wed, Feb 18, 2015 at 12:35 PM, Bryan Baugher <bjbq4d@gmail.com> wrote:
>>
>>> Hi everyone,
>>>
>>> The other day I ran into the issue mentioned here[1] about joining data
>>> with null values. This took awhile to figure out until I broke down and
>>> went to look at the docs to see if I was doing something obviously wrong. I
>>> used null values because I'm basically wanting to join two pcollections.
>>>
>>> Can crunch either throw an exception or log errors if I do something
>>> like this? Similarly would it be possible to get convenience methods for
>>> doing joins on PCollections?
>>>
>>> [1] - http://crunch.apache.org/user-guide.html#joins
>>>
>>
>>
>>
>> --
>> Director of Data Science
>> Cloudera <http://www.cloudera.com>
>> Twitter: @josh_wills <http://twitter.com/josh_wills>
>>
>


-- 
Director of Data Science
Cloudera <http://www.cloudera.com>
Twitter: @josh_wills <http://twitter.com/josh_wills>

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